Magnetic head for perpendicular magnetic recording and method of manufacturing same

ABSTRACT

A pole layer has an end face located in a medium facing surface, allows a magnetic flux corresponding to a magnetic field generated by a coil to pass therethrough, and generates a write magnetic field for writing data on a recording medium by using a perpendicular magnetic recording system. A shield incorporates: a first layer having an end face located in a region of the medium facing surface forward of the end face of the pole layer along the direction of travel of the recording medium; a second layer disposed in a region sandwiching the pole layer with the first layer; a first coupling portion coupling the first layer to the second layer without touching the pole layer; and a second coupling portion coupling the pole layer to the second layer and located farther from the medium facing surface than the first coupling portion.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a magnetic head for perpendicularmagnetic recording that is used for writing data on a recording mediumby means of a perpendicular magnetic recording system and to a method ofmanufacturing such a magnetic head.

2. Description of the Related Art

The recording systems of magnetic read/write devices include alongitudinal magnetic recording system wherein signals are magnetized inthe direction along the surface of the recording medium (thelongitudinal direction) and a perpendicular magnetic recording systemwherein signals are magnetized in the direction orthogonal to thesurface of the recording medium. It is known that the perpendicularmagnetic recording system is harder to be affected by thermalfluctuation of the recording medium and capable of implementing higherlinear recording density, compared with the longitudinal magneticrecording system.

Like magnetic heads for longitudinal magnetic recording, magnetic headsfor perpendicular magnetic recording typically used have a structure inwhich a reproducing (read) head having a magnetoresistive element (thatmay be hereinafter called an MR element) for reading and a recording(write) head having an induction-type electromagnetic transducer forwriting are stacked on a substrate. The write head comprises a magneticpole layer that produces a magnetic field in the direction orthogonal tothe surface of the recording medium.

For the perpendicular magnetic recording system, it is an improvement inrecording medium and an improvement in write head that mainlycontributes to an improvement in recording density. It is a reduction intrack width and an improvement in write characteristics that isparticularly required for the write head to achieve higher recordingdensity. On the other hand, if the track width is reduced, the writecharacteristics, such as an overwrite property that is a parameterindicating an overwriting capability, are degraded. It is thereforerequired to achieve better write characteristics as the track width isreduced.

A magnetic head used for a magnetic disk drive such as a hard disk driveis typically provided in a slider. The slider has a medium facingsurface that faces toward a recording medium. The medium facing surfacehas an air-inflow-side end and an air-outflow-side end. The sliderslightly flies over the surface of the recording medium by means of theairflow that comes from the air-inflow-side end into the space betweenthe medium facing surface and the recording medium. The magnetic head istypically disposed near the air-outflow-side end of the medium facingsurface of the slider. In a magnetic disk drive the magnetic head isaligned through the use of a rotary actuator, for example. In this case,the magnetic head moves over the recording medium along a circular orbitcentered on the center of rotation of the rotary actuator. In such amagnetic disk drive, a tilt called a skew of the magnetic head iscreated with respect to the tangent of the circular track, in accordancewith the position of the magnetic head across the tracks.

In a magnetic disk drive of the perpendicular magnetic recording systemthat exhibits a better capability of writing on a recording medium thanthe longitudinal magnetic recording system, in particular, if theabove-mentioned skew is created, problems arise, such as a phenomenon inwhich data stored on an adjacent track is erased when data is written ona specific track (that is hereinafter called adjacent track erasing) orunwanted writing is performed between adjacent two tracks. To achievehigher recording density, it is required to suppress adjacent trackerasing. Unwanted writing between adjacent two tracks affects detectionof servo signals for alignment of the magnetic head and thesignal-to-noise ratio of a read signal.

A technique is known for preventing the problems resulting from the skewas described above, as disclosed in U.S. Patent Application PublicationUS 2003/0151850 A1, for example. According to this technique, the endface of the pole layer located in the medium facing surface is made tohave a shape in which the side located backward along the direction oftravel of the recording medium (that is, the side located closer to theair inflow end of the slider) is shorter than the opposite side.

As a magnetic head for perpendicular magnetic recording, a magnetic headcomprising the pole layer and a shield is known, as disclosed in U.S.Pat. No. 4,656,546, for example. In the medium facing surface of thismagnetic head, an end face of the shield is located forward of the endface of the pole layer along the direction of travel of the recordingmedium with a specific small space therebetween. Such a magnetic headwill be hereinafter called a shield-type head. In the shield-type head,the shield prevents a magnetic flux from reaching the recording medium,the flux being generated from the end face of the pole layer andextending in directions except the direction orthogonal to the surfaceof the recording medium. In addition, the shield has a function ofreturning the magnetic flux that has been generated from the end face ofthe pole layer and has magnetized the recording medium. The shield-typehead achieves a further improvement in linear recording density.

U.S. Pat. No. 4,672,493 discloses a magnetic head having such astructure that magnetic layers are respectively provided forward andbackward of a middle magnetic layer to be a pole layer along thedirection of travel of a recording medium and that coils arerespectively provided between the middle magnetic layer and the magneticlayer located forward and between the middle magnetic layer and themagnetic layer located backward. According to the magnetic head, it ispossible to increase components in the direction orthogonal to thesurface of the recording medium among components of the magnetic fieldgenerated from an end of the middle magnetic layer closer to the mediumfacing surface.

Reference is now made to FIG. 43 to describe a basic configuration ofthe shield-type head. FIG. 43 is a cross-sectional view of the main partof an example of the shield-type head. This shield-type head comprises:a medium facing surface 100 that faces toward a recording medium; a coil101 for generating a magnetic field corresponding to data to be writtenon the medium; a pole layer 102 having an end located in the mediumfacing surface 100, allowing a magnetic flux corresponding to the fieldgenerated by the coil 101 to pass, and generating a write magnetic fieldfor writing the data on the medium by means of the perpendicularmagnetic recording system; a shield layer 103 having an end located inthe medium facing surface 100 and having a portion located away from themedium facing surface 100 and coupled to the pole layer 102; a gap layer104 provided between the pole layer 102 and the shield layer 103; and aninsulting layer 105 covering the coil 101. An insulating layer 106 isdisposed around the pole layer 102. The shield layer 103 is covered witha protection layer 107.

In the medium facing surface 100, the end of the shield layer 103 islocated forward of the end of the pole layer 102 along the direction Tof travel of the recording medium with a specific space created by thethickness of the gap layer 104. At least part of the coil 101 isdisposed between the pole layer 102 and the shield layer 103 andinsulated from the pole layer 102 and the shield layer 103.

The coil 101 is made of a conductive material such as copper. The polelayer 102 and the shield layer 103 are made of a magnetic material. Thegap layer 104 is made of an insulating material such as alumina (Al₂O₃).The insulating layer 105 is made of photoresist, for example.

In the head of FIG. 43, the gap layer 104 is disposed on the pole layer102 and the coil 101 is disposed on the gap layer 104. The coil 101 iscovered with the insulating layer 105. One of the ends of the insulatinglayer 105 closer to the medium facing surface 100 is located at adistance from the medium facing surface 100. In the region from themedium facing surface 100 to the end of the insulating layer 105 closerto the medium facing surface 100, the shield layer 103 faces toward thepole layer 102 with the gap layer 104 disposed in between. Throat heightTH is the length (height) of the portions of the pole layer 102 and theshield layer 103 facing toward each other with the gap layer 104disposed in between, the length being taken from the end closer to themedium facing surface 100 to the other end. The throat height THinfluences the intensity and distribution of the field generated fromthe pole layer 102 in the medium facing surface 100.

In the shield-type head as shown in FIG. 43, for example, it ispreferred to reduce the throat height TH to improve the overwriteproperty. It is required that the throat height TH be 0.1 to 0.3micrometer (μm), for example. When such a small throat height TH isrequired, the following two problems arise in the head of FIG. 43.

The first problem of the head of FIG. 43 is that it is difficult todefine the throat height TH with accuracy. The first problem will now bedescribed in detail. In the head of FIG. 43, the throat height TH isdefined by the thickness of a portion of the shield layer 103 locatedbetween the insulating layer 105 and the medium facing surface 100. Inaddition, the throat height TH is controlled by the depth to which themedium facing surface 100 is polished. However, the photoresistconstituting the insulating layer 105 has a relatively high thermalexpansion coefficient and is relatively soft. As a result, theinsulating layer 105 expands due to the heat produced when polishing isperformed, for example. In addition, the portion of the shield layer 103located between the insulating layer 105 and the medium facing surface100 is thin, particularly when the throat height TH is small.Furthermore, the end face of the shield layer 103 is exposed in a largeregion in the medium facing surface. Because of these factors,particularly in the case where the throat height TH is small, when themedium facing surface 100 is polished, the insulating layer 105 expandsand the end portion of the shield layer 103 closer to the medium facingsurface 100 tends to protrude. Consequently, the thickness of theportion of the shield layer 103 located between the insulating layer 105and the medium facing surface 100 varies when the medium facing surface100 is polished, which results in variations in throat height TH afterthe medium facing surface 100 is polished.

The second problem of the head of FIG. 43 is that, when the head isoperated, the insulating layer 105 expands due to the heat generated bythe coil 101, and the end portion of the shield layer 103 closer to themedium facing surface 100 thereby protrudes. The protrusion of the endportion of the shield layer 103 when the head is operated inducescollision of the slider with the recording medium.

For the shield-type head as shown in FIG. 43, for example, there aresome cases in which such a phenomenon noticeably arises that thereoccurs attenuation of signals written on one or more tracks adjacent tothe track that is a target of writing or reading in a wide range alongthe direction of track width (The phenomenon will be hereinafter calledwide-range adjacent track erase). It is assumed that one of reasons forthe wide-range adjacent track erase is that, as will be described later,no shield layer exists backward of the end face of the pole layer 102along the direction T of travel of the recording medium (that is, on aside of the end face of the pole layer 102 farther from the end face ofthe shield layer 103).

The magnetic flux that has been generated from the end face of the polelayer 102 and has magnetized the recording medium returns to the head.At this time, the magnetic flux is taken in by the shield layer 103 in aregion forward of the end face of the pole layer 102 along the directionT of travel of the recording medium, so that expansion of the magneticflux is suppressed. However, in a region backward of the end face of thepole layer 102 along the direction T of travel of the recording medium,the magnetic flux expands since no shield layer exists. It is assumedthat this causes the wide-range adjacent track erase.

Since a portion of the pole layer 102 near the medium facing surface 100defines the track width, this portion is smaller in width than the otherportion. As a result, there is a possibility that part of the magneticflux passing through the pole layer 102 leaks from the pole layer 102before reaching the end face of the pole layer 102. Since the leakageflux is taken in by the shield layer 103 in the region forward of theend face of the pole layer 102 along the direction T of travel of therecording medium, the leakage flux reaching the recording medium issuppressed. However, in a region backward of the end face of the polelayer 102 along the direction T of travel of the recording medium, theleakage flux reaches the recording medium since no shield layer exists.It is assumed that this is another cause of the wide-range adjacenttrack erase.

According to the magnetic head having a structure as disclosed in U.S.Pat. No. 4,672,493, it is assumed that it is possible to suppress thewide-range adjacent track erase caused by the foregoing factors.However, the magnetic head having such a structure is not capable ofsolving the foregoing problems, that is, the first problem that it isdifficult to define the throat height with accuracy and the secondproblem that the end portion of the shield layer closer to the mediumfacing surface protrudes due to the heat produced by the coil.

OBJECT AND SUMMARY OF THE INVENTION

It is an object of the invention to provide a magnetic head forperpendicular magnetic recording having a structure in which an end faceof a pole layer and an end face of a shield are adjacent to each otherwith a gap layer disposed in between in a medium facing surface, thehead being capable of defining the throat height with accuracy,suppressing protrusion of an end portion of the shield closer to themedium facing surface due to the heat produced by the coil, andsuppressing the wide-range adjacent track erase, and to provide a methodof manufacturing such a magnetic head.

A magnetic head for perpendicular magnetic recording of the inventioncomprises: a medium facing surface that faces toward a recording medium;a coil for generating a magnetic field corresponding to data to bewritten on the recording medium; a pole layer having an end face locatedin the medium facing surface, allowing a magnetic flux corresponding tothe field generated by the coil to pass therethrough, and generating awrite magnetic field for writing the data on the recording medium bymeans of a perpendicular magnetic recording system; and a shield.

The shield incorporates: a first layer having an end face located in aregion of the medium facing surface forward of the end face of the polelayer along a direction of travel of the recording medium; a secondlayer disposed in a region sandwiching the pole layer with the firstlayer; a first coupling portion coupling the first layer to the secondlayer without touching the pole layer; and a second coupling portioncoupling the pole layer to the second layer and located farther from themedium facing surface than the first coupling portion. The magnetic headfurther comprises a gap layer made of a nonmagnetic material anddisposed between the pole layer and the first layer. In the mediumfacing surface, the end face of the first layer is located at a specificdistance created by a thickness of the gap layer from the end face ofthe pole layer. The end face of the pole layer has a side locatedadjacent to the gap layer, the side defining the track width. Part ofthe coil passes through a space surrounded by the pole layer, the secondlayer, the first coupling portion and the second coupling portion.

A method of manufacturing the magnetic head for perpendicular magneticrecording of the invention comprises the steps of: forming the secondlayer; forming the coil; forming the first and second coupling portions;forming the pole layer; forming the gap layer on the pole layer; andforming the first layer on the gap layer.

According to the magnetic head for perpendicular magnetic recording ofthe invention or the method of manufacturing the same, the first andsecond layers of the shield are disposed in the regions sandwiching thepole layer. The first and second layers are coupled to each other by thefirst coupling portion, and the pole layer and the second layer arecoupled to each other by the second coupling portion. Part of the coilpasses through the space surrounded by the pole layer, the second layer,the first coupling portion and the second coupling portion.

In the magnetic head of the invention or the method of manufacturing thesame, the gap layer may have a thickness that falls within a range of 5to 60 nm inclusive.

In the magnetic head of the invention or the method of manufacturing thesame, each of the second layer and the first coupling portion may havean end face located in the medium facing surface.

In the magnetic head of the invention or the method of manufacturing thesame, the second layer may have an end face closer to the medium facingsurface, the end face being located at a distance from the medium facingsurface.

In the magnetic head of the invention or the method of manufacturing thesame, the first coupling portion may have an end face closer to themedium facing surface, the end face being located at a distance from themedium facing surface.

In the magnetic head of the invention or the method of manufacturing thesame, the first coupling portion may couple the first layer to thesecond layer on both sides of the pole layer opposed to each other inthe direction of track width. In this case, the first coupling portionmay incorporate: a first portion and a second portion that are connectedto the first layer and disposed on both sides of the pole layer opposedto each other in the direction of track width; and a third portioncoupling the second layer to the first and second portions and disposedbetween the medium facing surface and the part of the coil.

In the magnetic head of the invention or the method of manufacturing thesame, the shield may further incorporate a first side shield layer and asecond side shield layer that are connected to the first layer anddisposed on both sides of the pole layer opposed to each other in thedirection of track width, and each of the first and second side shieldlayers may have an end face located in the medium facing surface. Inthis case, the method may further comprise the step of forming the firstand second side shield layers performed between the step of forming thesecond layer and the step of forming the gap layer.

In the magnetic head of the invention or the method of manufacturing thesame, the coil may have a shape of flat whorl wound around the secondcoupling portion, or a helical shape wound around the pole layer.

The magnetic head of the invention may further comprise: an encasinglayer made of a nonmagnetic material and having a groove that opens in atop surface thereof and accommodates at least part of the pole layer;and a nonmagnetic conductive layer made of a nonmagnetic conductivematerial and disposed in the groove of the encasing layer between theencasing layer and the pole layer. The method of manufacturing themagnetic head of the invention may further comprise the steps of formingthe encasing layer and forming the nonmagnetic conductive layer. In thiscase, the nonmagnetic conductive layer may be formed by chemical vapordeposition in which formation of a single atomic layer is repeated. Thenonmagnetic conductive material may be Ta or Ru.

In the magnetic head of the invention or the method of manufacturing thesame, the pole layer may have a surface that bends, the surface touchingthe gap layer, and the gap layer may bend along the surface of the polelayer that bends. In this case, the gap layer may be formed by chemicalvapor deposition in which formation of a single atomic layer isrepeated. The nonmagnetic material forming the gap layer may be Ta, Ruor Al₂O₃.

According to the magnetic head for perpendicular magnetic recording ofthe invention or the method of manufacturing the same, the first andsecond layers of the shield are disposed in the regions sandwiching thepole layer. As a result, according to the invention, it is possible tosuppress the wide-range adjacent track erase. According to theinvention, part of the coil passes through the space surrounded by thepole layer, the second layer, the first coupling portion and the secondcoupling portion. As a result, according to the invention, it ispossible to suppress protrusion of the end portion of the first layercloser to the medium facing surface due to expansion of the insulatinglayer disposed around the coil. Consequently, the invention makes itpossible to define the throat height with accuracy and to suppressprotrusion of the end portion of the shield closer to the medium facingsurface due to the heat produced by the coil.

Other and further objects, features and advantages of the invention willappear more fully from the following description.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view illustrating a portion of a magnetic headof a first embodiment of the invention in a neighborhood of the mediumfacing surface.

FIG. 2 is a cross-sectional view for illustrating the configuration ofthe magnetic head of the first embodiment of the invention.

FIG. 3 is a front view of the medium facing surface of the magnetic headof the first embodiment of the invention.

FIG. 4 is a cross-sectional view taken along line 4-4 of FIG. 2.

FIG. 5 is a top view for illustrating the pole layer and the shield ofthe magnetic head of the first embodiment of the invention.

FIG. 6A to FIG. 6C are views for illustrating a step of a method ofmanufacturing the magnetic head of the first embodiment of theinvention.

FIG. 7A to FIG. 7C are views for illustrating a step that follows thestep shown in FIG. 6A to FIG. 6C.

FIG. 8A to FIG. 8C are views for illustrating a step that follows thestep shown in FIG. 7A to FIG. 7C.

FIG. 9A to FIG. 9C are views for illustrating a step that follows thestep shown in FIG. 8A to FIG. 8C.

FIG. 10A to FIG. 10C are views for illustrating a step that follows thestep shown in FIG. 9A to FIG. 9C.

FIG. 11A to FIG. 11C are views for illustrating a step that follows thestep shown in FIG. 10A to FIG. 10C.

FIG. 12A to FIG. 12C are views for illustrating a step that follows thestep shown in FIG. 11A to FIG. 11C.

FIG. 13A to FIG. 13C are views for illustrating a step that follows thestep shown in FIG. 12A to FIG. 12C.

FIG. 14A to FIG. 14C are views for illustrating a step that follows thestep shown in FIG. 13A to FIG. 13C.

FIG. 15A to FIG. 15C are views for illustrating a step that follows thestep shown in FIG. 14A to FIG. 14C.

FIG. 16A to FIG. 16C are views for illustrating a step that follows thestep shown in FIG. 15A to FIG. 15C.

FIG. 17A to FIG. 17C are views for illustrating a step that follows thestep shown in FIG. 16A to FIG. 16C.

FIG. 18 is a cross-sectional view for illustrating a step of a method ofmanufacturing a magnetic head of a first modification example of thefirst embodiment of the invention.

FIG. 19 is a cross-sectional view for illustrating a step that followsthe step shown in FIG. 18.

FIG. 20 is a cross-sectional view for illustrating a step that followsthe step shown in FIG. 19.

FIG. 21 is a cross-sectional view for illustrating a step that followsthe step shown in FIG. 20.

FIG. 22 is a cross-sectional view of a magnetic head of a secondmodification example of the first embodiment of the invention.

FIG. 23 is a front view of the medium facing surface of a magnetic headof a second embodiment of the invention.

FIG. 24 is a top view illustrating the pole layer and the shield of themagnetic head of the second embodiment of the invention.

FIG. 25 is a cross-sectional view for illustrating a step of a method ofmanufacturing the magnetic head of the second embodiment of theinvention.

FIG. 26 is a cross-sectional view for illustrating a step that followsthe step shown in FIG. 25.

FIG. 27 is a cross-sectional view for illustrating a step that followsthe step shown in FIG. 26.

FIG. 28 is a cross-sectional view for illustrating a step that followsthe step shown in FIG. 27.

FIG. 29 is a cross-sectional view for illustrating a step that followsthe step shown in FIG. 28.

FIG. 30 is a cross-sectional view of a magnetic head of a modificationexample of the second embodiment of the invention.

FIG. 31 is a perspective view illustrating a portion of a magnetic headof a third embodiment of the invention in a neighborhood of the mediumfacing surface.

FIG. 32 is a cross-sectional view of the magnetic head of the thirdembodiment of the invention.

FIG. 33 is a front view of the medium facing surface of the magnetichead of the third embodiment of the invention.

FIG. 34 is a front view of the medium facing surface of the magnetichead of the third embodiment of the invention.

FIG. 35 is a cross-sectional view of a magnetic head of a fourthembodiment of the invention.

FIG. 36 is a front view of the medium facing surface of the magnetichead of the fourth embodiment of the invention.

FIG. 37 is a cross-sectional view for illustrating a step of a method ofmanufacturing the magnetic head of the fourth embodiment of theinvention.

FIG. 38 is a cross-sectional view for illustrating a step that followsthe step shown in FIG. 37.

FIG. 39 is a cross-sectional view for illustrating a step that followsthe step shown in FIG. 38.

FIG. 40 is a cross-sectional view for illustrating a step that followsthe step shown in FIG. 39.

FIG. 41 is a cross-sectional view for illustrating a step that followsthe step shown in FIG. 40.

FIG. 42 is a cross-sectional view for illustrating a step that followsthe step shown in FIG. 41.

FIG. 43 is a cross-sectional view illustrating a main part of an exampleof the shield-type head.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First Embodiment

Preferred embodiments of the invention will now be described in detailwith reference to the accompanying drawings. Reference is now made toFIG. 1 to FIG. 5 to describe the configuration of a magnetic head forperpendicular magnetic recording of a first embodiment of the invention.FIG. 1 is a perspective view illustrating a portion of the magnetic headof the first embodiment in a neighborhood of the medium facing surface.FIG. 2 is a cross-sectional view for illustrating the configuration ofthe magnetic head of the embodiment. FIG. 2 illustrates a cross sectionorthogonal to the medium facing surface and a surface of a substrate.The arrow indicated with T in FIG. 2 shows the direction of travel of arecording medium. FIG. 3 is a front view of the medium facing surface ofthe magnetic head of the embodiment. FIG. 4 is a cross-sectional viewtaken along line 4-4 of FIG. 2. FIG. 5 is a top view for illustrating apole layer and a shield of the magnetic head of the embodiment.

As shown in FIG. 2 to FIG. 4, the magnetic head for perpendicularmagnetic recording (hereinafter simply called the magnetic head) of theembodiment comprises: a substrate 1 made of a ceramic such as aluminumoxide and titanium carbide (Al₂O₃—TiC); an insulating layer 2 made of aninsulating material such as alumina (Al₂O₃) and disposed on thesubstrate 1; a bottom shield layer 3 made of a magnetic material anddisposed on the insulating layer 2; a bottom shield gap film 4 that isan insulating film disposed on the bottom shield layer 3; amagnetoresistive (MR) element 5 as a read element disposed on the bottomshield gap film 4; a top shield gap film 6 that is an insulating filmdisposed on the MR element 5; and a top shield layer 7 made of amagnetic material and disposed on the top shield gap film 6.

The MR element 5 has an end that is located in the medium facing surface30 that faces toward a recording medium. The MR element 5 may be anelement made of a magneto-sensitive film that exhibits amagnetoresistive effect, such as an anisotropic magnetoresistive (AMR)element, a giant magnetoresistive (GMR) element, or a tunnelmagnetoresistive (TMR) element. The GMR element may be of acurrent-in-plane (CIP) type wherein a current used for detectingmagnetic signals is fed in the direction nearly parallel to the plane ofeach layer making up the GMR element, or may be of acurrent-perpendicular-to-plane (CPP) type wherein a current used fordetecting magnetic signals is fed in the direction nearly perpendicularto the plane of each layer making up the GMR element.

The portions from the bottom shield layer 3 to the top shield layer 7make up a read head. The magnetic head further comprises a nonmagneticlayer 8 made of a nonmagnetic material and disposed on the top shieldlayer 7, and a write head disposed on the nonmagnetic layer 8. Thenonmagnetic layer 8 is made of alumina, for example. The write headcomprises a coil 11, a pole layer 12, a shield 13 and a gap layer 14.

The coil 11 generates a magnetic field corresponding to data to bewritten on the recording medium. The pole layer 12 has an end facelocated in the medium facing surface 30. The pole layer 12 allows themagnetic flux corresponding to the field generated by the coil 11 topass therethrough and generates a write magnetic field for writing thedata on the medium by means of the perpendicular magnetic recordingsystem.

The shield 13 incorporates: a first layer 13A having an end face locatedin a region of the medium facing surface 30 forward of the end face ofthe pole layer 12 along the direction T of travel of the recordingmedium; a second layer 13B disposed in a region sandwiching the polelayer 12 with the first layer 13A; a first coupling portion 13C couplingthe first layer 13A to the second layer 13B without touching the polelayer 12; and a second coupling portion 13D located farther from themedium facing surface 30 than the first coupling portion 13C andcoupling the pole layer 12 to the second layer 13B. Each of the firstlayer 13A, the second layer 13B, the first coupling portion 13C and thesecond coupling portion 13D is made of a magnetic material. Such amaterial may be any of CoFeN, CoNiFe, NiFe and CoFe, for example.

The second layer 13B is disposed on the nonmagnetic layer 8. The secondlayer 13B has an end face closer to the medium facing surface 30. Thisend face is located at a distance from the medium facing surface 30. Themagnetic head further comprises: an insulating layer 21 made of aninsulating material and disposed around the second layer 13B on thenonmagnetic layer 8. The insulating layer 21 is made of alumina, forexample.

The first coupling portion 13C is disposed on a region of the secondlayer 13B near the medium facing surface 30. The first coupling portion13C has an end face closer to the medium facing surface 30. This endface is located at a distance from the medium facing surface 30. Thesecond coupling portion 13D is disposed on a region of the second layer13B farther from the medium facing surface 30 than the first couplingportion 13C.

The first coupling portion 13C has a first portion 13C1, a secondportion 13C2 and a third portion 13C3. The first portion 13C1 and thesecond portion 13C2 are connected to the first layer 13A and disposed onboth sides of the pole layer 12 opposed to each other in the directionof track width. The third portion 13C3 is disposed between the mediumfacing surface 30 and part of the coil 11, and couples the second layer13B to each of the first portion 13C1 and the second portion 13C2. Thefirst coupling portion 13C having the first to third portions 13C1, 13C2and 13C3 couples the first layer 13A to the second layer 13B atpositions on both sides of the pole layer 12 opposed to each other inthe direction of track width. The third portion 13C3 is disposed on thesecond layer 13B. The first portion 13C1 and the second portion 13C2 aredisposed on the third portion 13C3.

The magnetic head further comprises an insulating layer 22 made of aninsulating material and disposed on the second layer 13B. The coil 11 isdisposed on the insulating layer 22. The coil 11 is flat-whorl-shapedand wound around the second coupling portion 13D. The magnetic headfurther comprises: an insulating layer 23 made of an insulating materialand disposed around the coil 11 and in the space between the respectiveadjacent turns of the coil 11; and an insulating layer 24 disposedaround the insulating layer 23, the third portion 13C3 and the secondcoupling portion 13D. The third portion 13C3, the second couplingportion 13D, the coil 11, and the insulating layers 23 and 24 haveflattened top surfaces. The insulating layers 22 and 24 are made ofalumina, for example. The insulating layer 23 is made of photoresist,for example. The coil 11 is made of a conductive material such ascopper.

The magnetic head further comprises an encasing layer 25 made of anonmagnetic material and disposed on the flattened top surfaces of thethird portion 13C3, the second coupling portion 13D, the coil 11, andthe insulating layers 23 and 24. The encasing layer 25 has a groove 25 athat opens in the top surface thereof and that accommodates at leastpart of the pole layer 12. The bottom of the groove 25 a has a contacthole formed to a level of the top surface of the second coupling portion13D. The encasing layer 25 may be made of an insulating material such asalumina, silicon oxynitride (SiON) or silicon oxide (SiO_(x)), or anonmagnetic metal material such as Ru, Ta, Mo, Ti, W, NiCu, NiB or NiPd.

The magnetic head further comprises a nonmagnetic metal layer 26 made ofa nonmagnetic metal material and disposed on the top surface of theencasing layer 25. The nonmagnetic metal layer 26 has an opening 26 athat penetrates, and the edge of the opening 26 a is located directlyabove the edge of the groove 25 a in the top surface of the encasinglayer 25. The nonmagnetic metal layer 26 may be made of any of Ta, Mo,W, Ti, Ru, Rh, Re, Pt, Pd, Ir, NiCr, NiP, NiPd, NiB, AlCu, WSi₂, TaSi₂,TiSi₂, TiN, and TiW, for example.

The magnetic head further comprises a nonmagnetic film 27 and apolishing stopper layer 28 that are disposed in the groove 25 a of theencasing layer 25 and in the opening 26 a of the nonmagnetic metal layer26. The nonmagnetic film 27 is disposed to touch the surface of thegroove 25 a. The pole layer 12 is disposed apart from the surface of thegroove 25 a. The polishing stopper layer 28 is disposed between thenonmagnetic film 27 and the pole layer 12. The polishing stopper layer28 also functions as an electrode layer (a seed layer) used for formingthe pole layer 12 by plating. The nonmagnetic film 27 and the polishingstopper layer 28 have contact holes, too, that are formed to the levelof the top surface of the second coupling portion 13D. The pole layer 12is thus connected to the second coupling portion 13D through the contactholes formed in the groove 25 a, the nonmagnetic film 27 and thepolishing stopper layer 28.

The nonmagnetic film 27 is made of a nonmagnetic material. The materialof the nonmagnetic film 27 may be an insulating material, asemiconductor material or a conductive material. The insulating materialas the material of the nonmagnetic film 27 may be any of alumina,silicon oxide (SiO_(x)), and silicon oxynitride (SiON). Thesemiconductor material as the material of the nonmagnetic film 27 may bepolycrystalline silicon or amorphous silicon. The conductive material asthe material of the nonmagnetic film 27 may be the same as that of thenonmagnetic metal layer 26.

The polishing stopper layer 28 is made of a nonmagnetic material. Thematerial of the polishing stopper layer 28 may be a nonmagneticconductive material or an insulating material. The nonmagneticconductive material as the material of the polishing stopper layer 28may be the same as that of the nonmagnetic metal layer 26. Theinsulating material as the material of the polishing stopper layer 28may be silicon oxide. If the polishing stopper layer 28 is made of anonmagnetic conductive material, the polishing stopper layer 28corresponds to the nonmagnetic conductive layer of the invention.

The pole layer 12 is made of a magnetic metal material. The pole layer12 may be made of any of NiFe, CoNiFe and CoFe, for example.

The gap layer 14 is disposed on a region of the pole layer 12 near themedium facing surface 30. The gap layer 14 is made of a nonmagneticmaterial. The material of the gap layer 14 may be an insulating materialsuch as alumina or a nonmagnetic conductive material such as Ru, NiCu,Ta, W, NiB or NiPd. The first layer 13A of the shield 13 is disposed onthe gap layer 14.

In the medium facing surface 30, the end face of the first layer 13A islocated at a specific distance created by the thickness of the gap layer14 from the end face of the pole layer 12. The gap layer 14 preferablyhas a thickness that falls within a range of 5 to 60 nm inclusive, andthat may fall within a range of 30 to 60 nm inclusive, for example. Theend face of the pole layer 12 has a side adjacent to the gap layer 14,and this side defines the track width. Part of the coil 11 passesthrough the space surrounded by the pole layer 12, the second layer 13B,the first coupling portion 13C and the second coupling portion 13D.

The magnetic head further comprises: a yoke layer 15 disposed on aregion of the pole layer 12 apart from the medium facing surface 30; anda nonmagnetic layer 16 made of a nonmagnetic material and disposedaround the first layer 13A and the yoke layer 15. The nonmagnetic layer16 is made of alumina, for example. The first layer 13A, the yoke layer15 and the nonmagnetic layer 16 have flattened top surfaces.

The magnetic head further comprises a protection layer 17 made of anonmagnetic material and disposed on the top surfaces of the first layer13A, the yoke layer 15 and the nonmagnetic layer 16. The protectionlayer 17 is made of an inorganic insulating material such as alumina.

As described so far, the magnetic head of the embodiment comprises themedium facing surface 30 that faces toward a recording medium, the readhead, and the write head. The read head and the write head are stackedon the substrate 1. The read head is located backward along thedirection T of travel of the recording medium (that is, located closerto the air inflow end of the slider). The write head is located forwardalong the direction T of travel of the recording medium (that is,located closer to the air outflow end of the slider).

The read head comprises the MR element 5 as the read element, and thebottom shield layer 3 and the top shield layer 7 for shielding the MRelement 5. Portions of the bottom shield layer 3 and the top shieldlayer 7 that are located on a side of the medium facing surface 30 areopposed to each other, the MR element 5 being placed between theseportions. The read head further comprises: the bottom shield gap film 4disposed between the MR element 5 and the bottom shield layer 3; and thetop shield gap film 6 disposed between the MR element 5 and the topshield layer 7.

The write head comprises the coil 11, the pole layer 12, the shield 13and the gap layer 14.

The pole layer 12 is disposed in the groove 25 a of the encasing layer25 and in the opening 26 a of the nonmagnetic metal layer 26 with thenonmagnetic film 27 and the polishing stopper layer 28 disposed betweenthe pole layer 12 and each of the groove 25 a and the opening 26 a. Thenonmagnetic film 27 has a thickness that falls within a range of 10 to40 nm inclusive, for example. However, the thickness of the nonmagneticfilm 27 is not limited to this range but may be of any other value,depending on the track width. The polishing stopper layer 28 has athickness that falls within a range of 30 to 100 nm inclusive, forexample.

The pole layer 12 incorporates: a first portion having the end facelocated in the medium facing surface 30; and a second portion having athickness greater than that of the first portion and disposed fartherfrom the medium facing surface 30 than the first portion. The thicknessof the first portion does not change according to the distance from themedium facing surface 30. The top surface of the first portion islocated closer to the substrate 1 than the top surface of the secondportion. As a result, the top surface of the pole layer 12 that touchesthe gap layer 14 bends. The difference in level created between the topsurfaces of the first portion and the second portion falls within arange of 0.1 to 0.3 μm inclusive, for example. The thickness of thefirst portion falls within a range of 0.03 to 0.3 μm inclusive, forexample.

The shield 13 incorporates: the first layer 13A having the end facelocated in a region of the medium facing surface 30 forward of the endface of the pole layer 12 along the direction T of travel of therecording medium; the second layer 13B disposed in a region sandwichingthe pole layer 12 with the first layer 13A; the first coupling portion13C coupling the first layer 13A to the second layer 13B withouttouching the pole layer 12; and the second coupling portion 13D locatedfarther from the medium facing surface 30 than the first couplingportion 13C and coupling the pole layer 12 to the second layer 13B.

The first coupling portion 13C has the first portion 13C1, the secondportion 13C2 and the third portion 13C3. The first portion 13C1 and thesecond portion 13C2 are connected to the first layer 13A and disposed onboth sides of the pole layer 12 opposed to each other in the directionof track width. The third portion 13C3 is disposed between the mediumfacing surface 30 and a portion of the coil 11, and couples the secondlayer 13B to each of the first portion 13C1 and the second portion 13C2.

The first layer 13A has a thickness that falls within a range of 0.2 to0.6 μm inclusive, for example. The second layer 13B has a thickness thatfalls within a range of 0.5 to 1.5 μm inclusive, for example. Each ofthe first portion 13C1 and the second portion 13C2 has a thickness thatfalls within a range of 0.2 to 0.5 μm inclusive, for example. The thirdportion 13C3 has a thickness that falls within a range of 0.8 to 3.0 μminclusive, for example. The second coupling portion 13D has a thicknessthat falls within a range of 0.8 to 3.0 μm inclusive, for example.

Each of the second layer 13B and the first coupling portion 13C has anend face located closer to the medium facing surface 30, the end facebeing located at a distance from the medium facing surface 30. Thedistance between the medium facing surface 30 and each of the end faceof the second layer 13B and the end face of the first coupling portion13C is 0.1 to 0.8 μm, for example.

The bottom surface of the first layer 13A bends to be opposed to the topsurface of the pole layer 12 with the gap layer 14 disposed in between.The gap layer 14 also bends along the top surface of the pole layer 12.The width of the end face of the first layer 13A located in the mediumfacing surface 30 is equal to or greater than the track width.

Reference is now made to FIG. 1 and FIG. 5 to describe the shape of thepole layer 12 in detail. As shown in FIG. 5, the pole layer 12incorporates a track width defining portion 12A and a wide portion 12B.The track width defining portion 12A has the end face located in themedium facing surface 30. The wide portion 12B is located farther fromthe medium facing surface 30 than the track width defining portion 12Aand has a width greater than the width of the track width definingportion 12A. The width of the track width defining portion 12A does notchange in accordance with the distance from the medium facing surface30. The wide portion 12B is equal in width to the track width definingportion 12A at the boundary with the track width defining portion 12A,and gradually increases in width as the distance from the medium facingsurface 30 increases and then maintains a specific width to the end ofthe wide portion 12B. In the embodiment, the track width definingportion 12A is a portion of the pole layer 12 extending from the endface located in the medium facing surface 30 to the point at which thewidth of the pole layer 12 starts to increase. Here, the length of thetrack width defining portion 12A taken in the direction orthogonal tothe medium facing surface 30 is called a neck height. The neck heightfalls within a range of 0.05 to 0.3 μm inclusive, for example.

As shown in FIG. 3, the end face of the pole layer 12 located in themedium facing surface 30 has: a first side A1 closest to the substrate1; a second side A2 adjacent to the gap layer 14; a third side A3connecting an end of the first side A1 to an end of the second side A2;and a fourth side A4 connecting the other end of the first side A1 tothe other end of the second side A2. The second side A2 defines thetrack width. The width of the end face of the pole layer 12 located inthe medium facing surface 30 decreases as the distance from the firstside A1 decreases. Each of the third side A3 and the fourth side A4forms an angle that falls within a range of 5 to 15 degrees inclusive,for example, with respect to the direction orthogonal to the top surfaceof the substrate 1. The length of the second side A2, that is, the trackwidth, falls within a range of 0.05 to 0.20 μm inclusive, for example.

Throat height TH is the distance between the medium facing surface 30and one of two points that is closer to the medium facing surface 30,wherein one of the two points is the one at which the space between thepole layer 12 and the first layer 13A starts to increase when seen fromthe medium facing surface 30, and the other of the points is the one atwhich the gap layer 14 first bends when seen from the medium facingsurface 30. In the embodiment, as shown in FIG. 2, the throat height THis the distance between the medium facing surface 30 and the point atwhich the gap layer 14 first bends when seen from the medium facingsurface 30. The throat height TH falls within a range of 0.05 to 0.3 μminclusive, for example.

Reference is now made to FIG. 6A to FIG. 17A, FIG. 6B to FIG. 17B, andFIG. 6C to FIG. 17C to describe a method of manufacturing the magnetichead of the embodiment. FIG. 6A to FIG. 17A, FIG. 6B to FIG. 17B, andFIG. 6C to FIG. 17C illustrate layered structures obtained inmanufacturing process of the magnetic head. The portions closer to thesubstrate 1 than the top shield layer 7 are omitted in FIG. 6A to FIG.17A, FIG. 6B to FIG. 17B, and FIG. 6C to FIG. 17C. According to themethod of manufacturing the magnetic head of the embodiment, as shown inFIG. 2 to FIG. 4, the insulating layer 2, the bottom shield layer 3 andthe bottom shield gap film 4 are first formed one by one on thesubstrate 1. Next, the MR element 5 and leads (not shown) connected tothe MR element 5 are formed on the bottom shield gap film 4. Next, thetop shield gap film 6 is formed to cover the MR element 5 and the leads.Next, the top shield layer 7 is formed on the top shield gap film 6.

FIG. 6A to FIG. 6C illustrate the following step. FIG. 6A shows a crosssection of a layered structure obtained in the manufacturing process ofthe magnetic head, the cross section being orthogonal to the mediumfacing surface and the substrate. FIG. 6B shows a cross section of thelayered structure taken along line 6B-6B of FIG. 6A. FIG. 6C shows across section of the layered structure taken along line 6C-6C of FIG.6A.

In the step, first, the nonmagnetic layer 8 is formed on the top shieldlayer 7 by sputtering, for example. Next, the second layer 13B is formedon the nonmagnetic layer 8 by frame plating, for example. Next, theinsulating layer 21 is formed on the entire top surface of the layeredstructure. The insulating layer 21 is then polished by chemicalmechanical polishing (hereinafter referred to as CMP), for example, sothat the second layer 13B is exposed.

FIG. 7A to FIG. 7C illustrate the following step. FIG. 7A shows a crosssection of a layered structure obtained in the manufacturing process ofthe magnetic head, the cross section being orthogonal to the mediumfacing surface and the substrate. FIG. 7B shows a cross section of thelayered structure taken along line 7B-7B of FIG. 7A. FIG. 7C shows across section of the layered structure taken along line 7C-7C of FIG.7A.

In the step, first, the insulating layer 22 is formed on regions of thetop surfaces of the second layer 13B and the insulating layer 21 wherethe coil 11 is to be disposed. Next, the coil 11 is formed on theinsulating layer 22 by frame plating, for example. Next, the thirdportion 13C3 and the second coupling portion 13D are formed by frameplating, for example. Alternatively, the coil 11 may be formed after thethird portion 13C3 and the second coupling portion 13D are formed.

FIG. 8A to FIG. 8C illustrate the following step. FIG. 8A shows a crosssection of a layered structure obtained in the manufacturing process ofthe magnetic head, the cross section being orthogonal to the mediumfacing surface and the substrate. FIG. 8B shows a cross section of thelayered structure taken along line 8B-8B of FIG. 8A. FIG. 8C shows across section of the layered structure taken along line 8C-8C of FIG.8A.

In the step, first, the insulating layer 23 made of photoresist, forexample, is selectively formed around the coil 11 and in the spacebetween the respective adjacent turns of the coil 11. Next, theinsulating layer 24 having a thickness of 3 to 4 μm, for example, isformed by a method such as sputtering on the entire top surface of thelayered structure. Next, the insulating layer 24 is polished by CMP, forexample, so that the third portion 13C3, the second coupling portion 13Dand the coil 11 are exposed, and the top surfaces of the third portion13C3, the second coupling portion 13D, the coil 11, and the insulatinglayers 23 and 24 are thereby flattened.

FIG. 9A to FIG. 9C illustrate the following step. FIG. 9A shows a crosssection of a layered structure obtained in the manufacturing process ofthe magnetic head, the cross section being orthogonal to the mediumfacing surface and the substrate. FIG. 9B shows a cross section of thelayered structure taken along line 9B-9B of FIG. 9A. FIG. 9C shows across section of the layered structure taken along line 9C-9C of FIG.9A.

In the step, first, the first portion 13C1 and the second portion 13C2are formed on the third portion 13C2 by frame plating, for example.Next, a nonmagnetic layer 25P is formed by sputtering, for example, onthe entire top surface of the layered structure. The groove 25 a will beformed in the nonmagnetic layer 25P and the nonmagnetic layer 25P willbe thereby formed into the encasing layer 25 later. Next, thenonmagnetic layer 25P is polished so that the first portion 13C1 and thesecond portion 13C2 are exposed, and the top surfaces of the firstportion 13C1, the second portion 13C2 and the nonmagnetic layer 25P arethereby flattened.

FIG. 10A to FIG. 10C illustrate the following step. FIG. 10A shows across section of a layered structure obtained in the manufacturingprocess of the magnetic head, the cross section being orthogonal to themedium facing surface and the substrate. FIG. 10B shows a cross sectionof the layered structure taken along line 10B-10B of FIG. 10A. FIG. 10Cshows a cross section of the layered structure taken along line 10C-10Cof FIG. 10A.

In the step, first, the nonmagnetic metal layer 26 is formed bysputtering, for example, on the first portion 13C1, the second portion13C2 and the nonmagnetic layer 25P. The nonmagnetic metal layer 26 has athickness that falls within a range of 40 to 100 nm inclusive, forexample. Next, a photoresist layer having a thickness of 1.0 μm, forexample, is formed on the nonmagnetic metal layer 26. The photoresistlayer is then patterned to form a mask 31 for making the groove 25 a ofthe encasing layer 25. The mask 31 has an opening having a shapecorresponding to the groove 25 a.

FIG. 11A to FIG. 11C illustrate the following step. FIG. 11A shows across section of a layered structure obtained in the manufacturingprocess of the magnetic head, the cross section being orthogonal to themedium facing surface and the substrate. FIG. 11B shows a cross sectionof the layered structure taken along line 11B-11B of FIG. 11A. FIG. 11Cshows a cross section of the layered structure taken along line 11C-11Cof FIG. 11A.

In the step, first, the nonmagnetic metal layer 26 is selectivelyetched, using the mask 31. The opening 26 a that penetrates is therebyformed in the nonmagnetic metal layer 26. The opening 26 a has a shapecorresponding to the plane geometry of the pole layer 12 to be formedlater. Furthermore, a portion of the nonmagnetic layer 25P exposed fromthe opening 26 a of the nonmagnetic metal layer 26 is selectively etchedso as to form the groove 25 a in the nonmagnetic layer 25P. Furthermore,a portion of the nonmagnetic layer 25P located on the second couplingpotion 13D is selectively etched so as to form a contact hole at thebottom of the groove 25 a. The mask 31 is then removed. The nonmagneticlayer 25P is formed into the encasing layer 25 by forming the groove 25a therein. The edge of the opening 26 a of the nonmagnetic metal layer26 is located directly above the edge of the groove 25 a located in thetop surface of the encasing layer 25.

The etching of the nonmagnetic metal layer 26 and the nonmagnetic layer25P is performed by reactive ion etching or ion beam etching, forexample. The etching for forming the groove 25 a in the nonmagneticlayer 25P is performed such that the walls of the groove 25 acorresponding to both sides of the track width defining portion 12A ofthe pole layer 12 each form an angle that falls within a range of 5 to15 degrees inclusive, for example, with respect to the directionorthogonal to the top surface of the substrate 1.

FIG. 12A to FIG. 12C illustrate the following step. FIG. 12A shows across section of a layered structure obtained in the manufacturingprocess of the magnetic head, the cross section being orthogonal to themedium facing surface and the substrate. FIG. 12B shows a cross sectionof the layered structure taken along line 12B-12B of FIG. 12A. FIG. 12Cshows a cross section of the layered structure taken along line 12C-12Cof FIG. 12A.

In the step, first, the nonmagnetic film 27 is formed on the entire topsurface of the layered structure. The nonmagnetic film 27 is formed inthe groove 25 a of the encasing layer 25, too. The nonmagnetic film 27is formed by sputtering or chemical vapor deposition (hereinafterreferred to as CVD), for example. It is possible to control thethickness of the nonmagnetic film 27 with precision. It is therebypossible to control the track width with accuracy. If the nonmagneticfilm 27 is formed by CVD, it is preferred to employ a method called‘atomic layer CVD’ (ALCVD) in which formation of a single atomic layeris repeated. In this case, it is possible to control the thickness ofthe nonmagnetic film 27 with higher precision. When ALCVD is employed toform the nonmagnetic film 27, it is preferred to use alumina, amonginsulating materials and Ta or Ru among conductive materials as thematerial of the nonmagnetic film 27. If a semiconductor material isselected as the material of the nonmagnetic film 27, it is preferred toform the nonmagnetic film 27 by ALCVD at a low temperature (around 200°C.) or by low-pressure CVD at a low temperature. The semiconductormaterial as the material of the nonmagnetic film 27 is preferablyundoped polycrystalline silicon or amorphous silicon.

Next, the polishing stopper layer 28 is formed on the entire top surfaceof the layered structure. The polishing stopper layer 28 is formed inthe groove 25 a of the encasing layer 25, too. The polishing stopperlayer 28 indicates the level at which polishing of the polishing step tobe performed later is stopped. If the nonmagnetic film 27 is made of aconductive material, it is possible to make the nonmagnetic film 27function as the polishing stopper layer 28, too, without providing thepolishing stopper layer 28. In this case, the nonmagnetic film 27corresponds to the nonmagnetic conductive layer of the invention.

If a nonmagnetic conductive material is used as the material of thepolishing stopper layer 28, the polishing stopper layer 28 is formed bysputtering or CVD, for example. If the polishing stopper layer 28 isformed by CVD, it is preferred to employ ALCVD. If the polishing stopperlayer 28 made of a nonmagnetic conductive material is formed by ALCVD,Ta or Ru is preferred as the material of the polishing stopper layer 28.The polishing stopper layer 28 formed by ALCVD exhibits a good stepcoverage. Therefore, it is possible to form the polishing stopper layer28 that is uniform in the groove 25 a of the encasing layer 25 byemploying ALCVD to form the polishing stopper layer 28. It is therebypossible to control the track width with accuracy. If the polishingstopper layer 28 is formed by ALCVD, the nonmagnetic film 27 forcontrolling the track width may be omitted.

If the polishing stopper layer 28 made of a nonmagnetic conductivematerial is formed by ALCVD, it is possible to reduce the resistance ofthe electrode layer (seed layer) used for forming the pole layer 12 byplating. It is thereby possible to form the pole layer 12 having aprecise thickness.

Next, portions of the nonmagnetic film 27 and the polishing stopperlayer 28 located on the second coupling portion 13D are selectivelyetched to form the contact holes in the nonmagnetic film 27 and thepolishing stopper layer 28.

Next, a magnetic layer 12P that will be the pole layer 12 later isformed on the entire top surface of the layered structure. The magneticlayer 12P is formed by the following method, for example. First, anelectrode film to be a portion of an electrode layer (seed layer) forplating is formed on the entire top surface of the layered structure.The electrode film is made of a magnetic material and will be a portionof the pole layer 12 later. The electrode film is formed by sputteringor ion beam deposition (hereinafter referred to as IBD), for example. Ifthe electrode film is formed by sputtering, it is preferred to employcollimation sputtering or long throw sputtering. Alternatively, thepolishing stopper layer 28 may be used as an electrode layer (seedlayer) for plating instead of forming the electrode film made of amagnetic material. Next, a plating layer is formed on the electrode filmby frame plating, for example. The plating layer has a thickness of 0.5to 1.0 μm, for example. The plating layer is made of a magnetic materialand will be a major portion of the pole layer 12 later. The platinglayer is formed such that the top surface thereof is located higher thanthe top surfaces of the nonmagnetic metal layer 26, the nonmagnetic film27 and the polishing stopper layer 28.

Next, a coating layer 32 made of alumina, for example, and having athickness of 0.5 to 1.2 μm, for example, is formed by a method such assputtering on the entire top surface of the layered structure.

FIG. 13A to FIG. 13C illustrate the following step. FIG. 13A shows across section of a layered structure obtained in the manufacturingprocess of the magnetic head, the cross section being orthogonal to themedium facing surface and the substrate. FIG. 13B shows a cross sectionof the layered structure taken along line 13B-13B of FIG. 13A. FIG. 13Cshows a cross section of the layered structure taken along line 13C-13Cof FIG. 13A.

In the step, first, the coating layer 32 and the magnetic layer 12P arepolished by CMP, for example, so that the polishing stopper layer 28 isexposed, and the top surfaces of the polishing stopper layer 28 and themagnetic layer 12P are thereby flattened. If the coating layer 32 andthe magnetic layer 12P are polished by CMP, such a slurry is used thatpolishing is stopped when the polishing stopper layer 28 is exposed,such as an alumina-base slurry.

FIG. 14A to FIG. 14C illustrate the following step. FIG. 14A shows across section of a layered structure obtained in the manufacturingprocess of the magnetic head, the cross section being orthogonal to themedium facing surface and the substrate. FIG. 14B shows a cross sectionof the layered structure taken along line 14B-14B of FIG. 14A. FIG. 14Cshows a cross section of the layered structure taken along line 14C-14Cof FIG. 14A.

In the step, first, a photoresist layer is formed on the entire topsurface of the layered structure. The photoresist layer is thenpatterned to form a mask 33 for etching a portion of the magnetic layer12P. The mask 33 covers a portion of the top surface of the magneticlayer 12P that will be the top surface of the second portion of the polelayer 12 later. Next, the portion of the magnetic layer 12P is etched byion beam etching, for example, using the mask 33. The magnetic layer 12Pis thereby formed into the pole layer 12. This etching is performed suchthat the second side A2 of the end face of the pole layer 12 located inthe medium facing surface 30 is located at a level that falls within arange between the height of the top surface of the nonmagnetic metallayer 26 as initially formed and the height of the bottom surfacethereof. Therefore, the nonmagnetic metal layer 26 serves as thereference indicating the level at which this etching is stopped. Theportion of the magnetic layer 12P is etched by the foregoing manner, sothat each of the track width and the thickness of the pole layer 12taken in the medium facing surface 30 is controlled to be nearlyuniform. It is thereby possible to control the thickness of the polelayer 12 and the track width with precision. Next, the mask 33 isremoved.

FIG. 15A to FIG. 15C illustrate the following step. FIG. 15A shows across section of a layered structure obtained in the manufacturingprocess of the magnetic head, the cross section being orthogonal to themedium facing surface and the substrate. FIG. 15B shows a cross sectionof the layered structure taken along line 15B-15B of FIG. 15A. FIG. 15Cshows a cross section of the layered structure taken along line 15C-15Cof FIG. 15A.

In the step, first, the gap layer 14 is formed on the entire top surfaceof the layered structure. The gap layer 14 is formed by sputtering orCVD, for example. If the gap layer 14 is formed by CVD, it is preferredto employ ALCVD. If the gap layer 14 is formed by ALCVD, the material ofthe gap layer 14 is preferably alumina among insulating materials, or Taor Ru among conductive materials. The gap layer 14 formed by ALCVDexhibits a good step coverage. Therefore, it is possible to form the gaplayer 14 that is thin and uniform on the bending top surface of the polelayer 12 by employing ALCVD to form the gap layer 14.

Next, a photoresist layer is formed on the entire top surface of thelayered structure. The photoresist layer is then patterned to form amask 34. The mask 34 covers a portion of the gap layer 14 to be left.Next, the gap layer 14, the nonmagnetic metal layer 26, the nonmagneticfilm 27 and the polishing stopper layer 28 are selectively etched, usingthe mask 34. As a result, the top surfaces of the first portion 13C1 andthe second portion 13C2 are exposed, and a portion of the top surface ofthe pole layer 12 is exposed. Next, the mask 34 is removed.

FIG. 16A to FIG. 16C illustrate the following step. FIG. 16A shows across section of a layered structure obtained in the manufacturingprocess of the magnetic head, the cross section being orthogonal to themedium facing surface and the substrate. FIG. 16B shows a cross sectionof the layered structure taken along line 16B-16B of FIG. 16A. FIG. 16Cshows a cross section of the layered structure taken along line 16C-16Cof FIG. 16A.

In the step, first, the first layer 13A is formed on the first portion13C1, the second portion 13C2 and the gap layer 14. At the same time,the yoke layer 15 is formed on the pole layer 12. The first layer 13Aand the yoke layer 15 may be formed by frame plating or by making amagnetic layer through sputtering and then selectively etching themagnetic layer. Next, the nonmagnetic layer 16 is formed on the entiretop surface of the layered structure. Next, the nonmagnetic layer 16 ispolished by CMP, for example, so that the first layer 13A and the yokelayer 15 are exposed, and the top surfaces of the first layer 13A, theyoke layer 15 and the nonmagnetic layer 16 are flattened. The yoke layer15 polished has a thickness of 0.25 to 0.45 μm, for example.Alternatively, the above-mentioned step of flattening the top surfacesof the first layer 13A, the yoke layer 15 and the nonmagnetic layer 16may be omitted, so that the first layer 13A and the yoke layer 15 havethe shapes as initially formed.

FIG. 17A to FIG. 17C illustrate the following step. FIG. 17A shows across section of a layered structure obtained in the manufacturingprocess of the magnetic head, the cross section being orthogonal to themedium facing surface and the substrate. FIG. 17B shows a cross sectionof the layered structure taken along line 17B-17B of FIG. 17A. FIG. 17Cshows a cross section of the layered structure taken along line 17C-17Cof FIG. 17A.

In the step, first, the protection layer 17 is formed to cover theentire top surface of the layered structure. Wiring and terminals arethen formed on the protection layer 17, the substrate is cut intosliders, and the steps including polishing of the medium facing surface30 and fabrication of flying rails are performed. The magnetic head isthus completed.

The operation and effects of the magnetic head of the embodiment willnow be described. The magnetic head writes data on a recording medium byusing the write head and reads data written on the recording medium byusing the read head. In the write head, the coil 11 generates a magneticfield that corresponds to the data to be written on the medium. The polelayer 12 and the shield 13 form a magnetic path through which a magneticflux corresponding to the magnetic field generated by the coil 11passes. The pole layer 12 allows the flux corresponding to the fieldgenerated by the coil 11 to pass and generates a write magnetic fieldused for writing the data on the medium by means of the perpendicularmagnetic recording system. The shield 13 takes in a disturbance magneticfield applied from outside the magnetic head to the magnetic head. It isthereby possible to prevent erroneous writing on the recording mediumcaused by the disturbance magnetic field intensively taken in into thepole layer 12. Furthermore, the shield 13 has a function of preventing amagnetic flux from reaching the recording medium, the flux beinggenerated from the end face of the pole layer 12 and extending indirections except the direction orthogonal to the surface of therecording medium. The shield 13 also has a function of returning amagnetic flux that has been generated from the end face of the polelayer 12 and has magnetized the recording medium.

The shield 13 incorporates: the first layer 13A having the end facelocated in a region of the medium facing surface 30 forward of the endface of the pole layer 12 along the direction T of travel of therecording medium; the second layer 13B disposed in a region sandwichingthe pole layer 12 with the first layer 13A; the first coupling portion13C coupling the first layer 13A to the second layer 13B withouttouching the pole layer 12; and the second coupling portion 13D locatedfarther from the medium facing surface 30 than the first couplingportion 13C and coupling the pole layer 12 to the second layer 13B. Thefirst coupling portion 13C has the first portion 13C1, the secondportion 13C2 and the third portion 13C3. The first portion 13C1 and thesecond portion 13C2 are connected to the first layer 13A and disposed onboth sides of the pole layer 12 opposed to each other in the directionof track width. The third portion 13C3 is disposed between the mediumfacing surface 30 and part of the coil 11 and couples the second layer13B to each of the first portion 13C1 and the second portion 13C2.

As thus described, in the embodiment, the first layer 13A and the secondlayer 13B of the shield 13 are located in the regions sandwiching thepole layer 12 in between. Therefore, according to the embodiment, it ispossible to suppress expansion of the magnetic flux in regions bothforward and backward of the end face of the pole layer 12 along thedirection T of travel of the recording medium and to suppress leakageflux reaching the recording medium. It is thereby possible to suppressthe wide-range adjacent track erase.

According to the embodiment, part of the coil 11 passes through thespace surrounded by the pole layer 12, the second layer 13B, the firstcoupling portion 13C and the second coupling portion 13D. It is therebypossible to prevent the end portion of the first layer 13A closer to themedium facing surface 30 from protruding in response to expansion of theinsulating layer 23 disposed around the coil 11. As a result, accordingto the embodiment, it is possible to define the throat height TH withaccuracy and to suppress protrusion of the end portion of the shield 13closer to the medium facing surface 30, that is, the end portion of thefirst layer 13A closer to the medium facing surface 30, due to the heatproduced by the coil 11.

According to the embodiment, in the medium facing surface 30, the endface of the first layer 13A is located forward of the end face of thepole layer 12 along the direction T of travel of the recording medium(that is, located closer to the air outflow end of the slider) with aspecific small space created by the gap layer 14. The location of an endof the bit pattern written on the recording medium is determined by thelocation of the end of the pole layer 12 that is closer to the gap layer14 and located in the medium facing surface 30. The first layer 13Atakes in a magnetic flux generated from the end face of the pole layer12 located in the medium facing surface 30 and extending in directionsexcept the direction orthogonal to the surface of the recording mediumso as to prevent the flux from reaching the recording medium. It isthereby possible to prevent a direction of magnetization of the bitpattern already written on the medium from being changed due to theeffect of the above-mentioned flux. According to the embodiment, animprovement in linear recording density is thus achieved.

According to the embodiment, each of the second layer 13B and the firstcoupling portion 13C has the end face located closer to the mediumfacing surface 30, the end face being located at a distance from themedium facing surface 30. The insulating layer 21 is disposed betweenthe medium facing surface 30 and the end face of the second layer 13Bcloser to the medium facing surface 30. The insulating layer 24 and theencasing layer 25 are disposed between the medium facing surface 30 andthe end face of the first coupling portion 13C closer to the mediumfacing surface 30. As a result, according to the embodiment, it ispossible to suppress protrusion of the end face of each of the secondlayer 13B and the first coupling portion 13C in response to expansion ofthe insulating layer 23 disposed around the coil 11.

According to the embodiment, the throat height TH is not defined by theend of the first layer 13A farther from the medium facing surface 30 butdefined by the point at which the gap layer 14 first bends when seenfrom the medium facing surface 30, that is, the point at which thebottom surface of the first layer 13A first bends when seen from themedium facing surface 30. As a result, it is possible to reduce thethroat height TH while the volume of the first layer 13A is sufficientlyincreased. It is thereby possible to improve the overwrite property.

According to the embodiment, as shown in FIG. 3, the end face of thepole layer 12 located in the medium facing surface 30 has a width thatdecreases as the distance from the first side A1 decreases. It isthereby possible to prevent the problems resulting from the skew.

According to the embodiment, the pole layer 12 is disposed in the groove25 a of the encasing layer 25 made of a nonmagnetic material with thenonmagnetic film 27 and the polishing stopper layer 28 disposed betweenthe pole layer 12 and the groove 25 a. Consequently, the pole layer 12is smaller than the groove 25 a in width. It is thereby possible toeasily form the groove 25 a and to easily reduce the width of the polelayer 12 and the width of the top surface of the track width definingportion 12A that defines the track width, in particular. As a result,according to the embodiment, it is possible to easily implement thetrack width that is smaller than the minimum track width that can beformed by photolithography and to control the track width with accuracy.

MODIFICATION EXAMPLES

First and second modification examples of the embodiment will now bedescribed. Reference is now made to FIG. 18 to FIG. 21 to describe amethod of manufacturing a magnetic head of the first modificationexample. FIG. 18 to FIG. 21 each illustrate a cross section of a layeredstructure obtained in manufacturing process of the magnetic headorthogonal to the medium facing surface and the substrate. In FIG. 18 toFIG. 21 the portions closer to the substrate 1 than the top shield layer7 are omitted.

FIG. 18 illustrates the step that follows the step shown in FIG. 13A toFIG. 13C. In the step, first, a nonmagnetic film 41 made of anonmagnetic material such as alumina is formed by sputtering, forexample, on the entire top surface of the layered structure. Next, aphotoresist layer is formed on the entire top surface of the layeredstructure. The photoresist layer is then patterned to form a mask 42 foretching portions of the magnetic layer 12P and the nonmagnetic film 41.Next, the portion of the nonmagnetic film 41 is etched by reactive ionetching, for example, using the mask 42. Next, the portion of themagnetic layer 12P is etched by ion beam etching, for example, using themask 42. The magnetic layer 12P is thereby formed into the pole layer12. This etching is performed such that the second side A2 of the endface of the pole layer 12 located in the medium facing surface 30 islocated at a level that falls within a range between the height of thetop surface of the nonmagnetic metal layer 26 as initially formed andthe height of the bottom surface thereof. Next, the mask 42 is removed.Next, as shown in FIG. 19, the gap layer 14 is formed on the entire topsurface of the layered structure.

FIG. 20 illustrates the following step. In the step, first, aphotoresist layer is formed on the entire top surface of the layeredstructure. The photoresist layer is then patterned to form a mask 43.The mask 43 covers a portion of the gap layer 14 to be left. Next, thegap layer 14, the nonmagnetic film 41, the nonmagnetic metal layer 26,the nonmagnetic film 27 and the polishing stopper layer 28 areselectively etched, using the mask 43. As a result, the top surfaces ofthe first portion 13C1 and the second portion 13C2 are exposed, and aportion of the top surface of the pole layer 12 is exposed. Next, themask 43 is removed.

FIG. 21 illustrates the following step. In the step, first, the firstlayer 13A is formed on the first portion 13C1, the second portion 13C2and the gap layer 14. At the same time, the yoke layer 15 is formed onthe pole layer 12. Next, the nonmagnetic layer 16 is formed on theentire top surface of the layered structure. Next, the nonmagnetic layer16 is polished by CMP, for example, so that the first layer 13A and theyoke layer 15 are exposed, and the top surfaces of the first layer 13A,the yoke layer 15 and the nonmagnetic layer 16 are flattened. Next,although not shown, the protection layer 17 is formed to cover theentire top surface of the layered structure. Wiring and terminals arethen formed on the protection layer 17, the substrate is cut intosliders, and the steps including polishing of the medium facing surface30 and fabrication of flying rails are performed. The magnetic head isthus completed.

In the magnetic head of the first modification example, the gap layer 14and the nonmagnetic film 41 are disposed between the pole layer 12 andthe first layer 13A in the region farther from the medium facing surface30 than the point at which the gap layer 14 first bends when seen fromthe medium facing surface 30. Therefore, flux leakage in this regionbetween the pole layer 12 and the first layer 13A is less, compared withthe case in which the nonmagnetic film 41 is not provided. As a result,it is possible to introduce a magnetic flux of greater magnitude to themedium facing surface 30 and to thereby improve the overwrite property.The remainder of configuration, function and effects of the magnetichead of the first modification example are similar to those of themagnetic head of FIG. 1 to FIG. 5.

FIG. 22 illustrates a cross section of a magnetic head of the secondmodification example orthogonal to the medium facing surface and thesubstrate. The magnetic head comprises a helical coil wound around thepole layer 12 in place of the flat-whorl-shaped coil 11 of FIG. 2. Thecoil incorporates: a lower layer 45A disposed on the insulating layer22; an upper layer 45B disposed above the pole layer 12; and a couplingportion not shown that couples the lower layer 45A to the upper layer45B. In the magnetic head of the second modification example, aninsulating layer 46 is disposed on the first layer 13A, the pole layer12 and the yoke layer 15. The upper layer 45B is disposed on theinsulating layer 46 and covered with the protection layer 17.

According to the second modification example, it is possible to make theresistance of the helical coil lower, compared with the resistance ofthe flat-whorl-shaped coil 11. It is thereby possible to furthersuppress protrusion of the end portion of the shield 13 closer to themedium facing surface 30, that is, the end portion of the first layer13A closer to the medium facing surface 30, due to the heat produced bythe coil. As a result, it is possible to reduce the distance between theslider and the recording medium and to thereby improve the performanceof the magnetic head. The remainder of configuration, function andeffects of the magnetic head of the second modification example aresimilar to those of the magnetic head of FIG. 1 to FIG. 5.

Second Embodiment

A magnetic head and a method of manufacturing the same of a secondembodiment of the invention will now be described. Reference is now madeto FIG. 23 and FIG. 24 to describe the configuration of the magnetichead of the second embodiment. FIG. 23 is a front view of the mediumfacing surface of the magnetic head of the embodiment. FIG. 24 is a planview illustrating the pole layer and the shield of the magnetic head ofthe embodiment.

As shown in FIG. 23 and FIG. 24, the shield 13 of the magnetic head ofthe second embodiment incorporates a first side shield layer 13E and asecond side shield layer 13F in addition to the first layer 13A, thesecond layer 13B, the first coupling portion 13C and the second couplingportion 13D. The side shield layers 13E and 13F are connected to thefirst layer 13A and disposed on both sides of the pole layer 12 opposedto each other in the direction of track width. Each of the side shieldlayers 13E and 13F has an end face located in the medium facing surface30. Each of the side shield layers 13E and 13F is made of a magneticmaterial. The material of the side shield layers 13E and 13F may be thesame as that of the pole layer 12.

In the second embodiment, the encasing layer 25 has grooves 25 b and 25c in addition to the groove 25 a, wherein the grooves 25 b and 25 c openin the top surface of the encasing layer 25 and accommodate the sideshield layers 13E and 13F. The nonmagnetic metal layer 26 has openings26 b and 26 c in addition to the opening 26 a. The edges of the openings26 b and 26 c are located directly above the edges of the grooves 25 band 25 c in the top surface of the encasing layer 25. The nonmagneticfilm 27 and the polishing stopper layer 28 are located in the groove 25b and the opening 26 b and in the groove 25 c and the opening 26 c, inaddition to the groove 25 a and the opening 26 a. The nonmagnetic film27 is disposed to touch the surfaces of the grooves 25 b and 25 c. Theside shield layers 13E and 13F are disposed apart from the surfaces ofthe grooves 25 b and 25 c, respectively. The polishing stopper layer 28is disposed between the nonmagnetic film 27 and the side shield layers13E and 13F.

Reference is now made to FIG. 25 to FIG. 29 to describe a method ofmanufacturing the magnetic head of the second embodiment. FIG. 25 toFIG. 29 are cross-sectional views of layered structures obtained inmanufacturing process of the magnetic head. FIG. 25 to FIG. 29 showcross sections of portions of the layered structures near the mediumfacing surface, the cross sections being parallel to the medium facingsurface. The portions closer to the substrate 1 than the top shieldlayer 7 are omitted in FIG. 25 to FIG. 29.

The method of manufacturing the magnetic head of the second embodimentincludes the steps up to the step of flattening the top surfaces of thefirst portion 13C1, the second portion 13C2 and the nonmagnetic layer25P as shown in FIG. 9A to FIG. 9C that are the same as those of thefirst embodiment.

FIG. 25 illustrates the following step. In the step, first, thenonmagnetic metal layer 26 is formed by sputtering, for example, on thefirst portion 13C1, the second portion 13C2 and the nonmagnetic layer25P as in the first embodiment. Next, a photoresist layer having athickness of 1.0 μm, for example, is formed on the nonmagnetic metallayer 26. The photoresist layer is then patterned to form the mask 31for making the grooves 25 a, 25 b and 25 c of the encasing layer 25. Themask 31 has three openings having shapes corresponding to the grooves 25a, 25 b and 25 c, respectively.

Next, the nonmagnetic metal layer 26 is selectively etched, using themask 31. The openings 26 a, 26 b and 26 c that penetrate are therebyformed in the nonmagnetic metal layer 26. The openings 26 a, 26 b and 26c have shapes corresponding to the plane geometries of the pole layer 12and the side shield layers 13E and 13F, respectively, to be formedlater. Furthermore, portions of the nonmagnetic layer 25P exposed fromthe openings 26 a, 26 b and 26 c of the nonmagnetic metal layer 26 areselectively etched so as to form the grooves 25 a, 25 b and 25 c in thenonmagnetic layer 25P. Furthermore, a portion of the nonmagnetic layer25P located on the second coupling potion 13D is selectively etched soas to form a contact hole in the bottom surface of the groove 25 a. Themask 31 is then removed. The nonmagnetic layer 25P is formed into theencasing layer 25 by forming the grooves 25 a, 25 b and 25 c therein.The edges of the openings 26 a, 26 b and 26 c of the nonmagnetic metallayer 26 are respectively located directly above the edges of thegrooves 25 a, 25 b and 25 c located in the top surface of the encasinglayer 25. Each of the nonmagnetic metal layer 26 and the nonmagneticlayer 25P is etched by a method the same as that of the firstembodiment.

FIG. 26 illustrates the following step. In the step, first, thenonmagnetic film 27 is formed on the entire top surface of the layeredstructure. The nonmagnetic film 27 is formed in the grooves 25 a, 25 band 25 c of the encasing layer 25, too. Next, the polishing stopperlayer 28 is formed on the entire top surface of the layered structure.The polishing stopper layer 28 is formed in the grooves 25 a, 25 b and25 c of the encasing layer 25, too. The polishing stopper layer 28indicates the level at which polishing of the polishing step to beperformed later is stopped. Each of the nonmagnetic film 27 and thepolishing stopper layer 28 is formed by a method the same as that of thefirst embodiment. Next, portions of the nonmagnetic film 27 and thepolishing stopper layer 28 located on the second coupling portion 13Dare selectively etched to form contact holes in the nonmagnetic film 27and the polishing stopper layer 28.

Next, a magnetic layer 12P to be the pole layer 12 is formed on theentire top surface of the layered structure. The magnetic layer 12P isformed by a method the same as that of the first embodiment. Next, thecoating layer 32 made of alumina, for example, and having a thickness of0.5 to 1.2 μm, for example, is formed on the entire top surface of thelayered structure.

FIG. 27 illustrates the following step. In the step, first, the coatinglayer 32 and the magnetic layer 12P are polished by CMP, for example, sothat the polishing stopper layer 28 is exposed, and the top surfaces ofthe polishing stopper layer 28 and the magnetic layer 12P are therebyflattened. If the coating layer 32 and the magnetic layer 12P arepolished by CMP, such a slurry is used that polishing is stopped whenthe polishing stopper layer 28 is exposed, such as an alumina-baseslurry. Next, a portion of the magnetic layer 12P is etched by a methodthe same as the step illustrated in FIG. 14A to FIG. 14C of the firstembodiment. The magnetic layer 12P is thereby formed into the pole layer12 and the side shield layers 13E and 13F.

FIG. 28 illustrates the following step. In the step, first, the gaplayer 14 is formed on the entire top surface of the layered structure.The gap layer 14 is formed by a method the same as that of the firstembodiment. Next, a photoresist layer is formed on the entire topsurface of the layered structure. The photoresist layer is thenpatterned to form the mask 34. The mask 34 covers a portion of the gaplayer 14 to be left. The mask 34 of the second embodiment has twoopenings having shapes corresponding to the shapes of the side shieldlayers 13E and 13F. Next, the gap layer 14, the nonmagnetic metal layer26, the nonmagnetic film 27 and the polishing stopper layer 28 areselectively etched, using the mask 34. As a result, the top surfaces ofthe first portion 13C1, the second portion 13C2, and the side shieldlayers 13E and 13F are exposed, and a portion of the top surface of thepole layer 12 is exposed. Next, the mask 34 is removed.

FIG. 29 illustrates the following step. In the step, first, as in thestep illustrated in FIG. 16A to FIG. 16C of the first embodiment, thefirst layer 13A is formed on the first portion 13C1, the second portion13C2 and the gap layer 14. At the same time, the yoke layer 15 is formedon the pole layer 12. In the second embodiment, the first layer 13Atouches the top surfaces of the side shield layers 13E and 13F. Next, asin the step illustrated in FIG. 16A to FIG. 16C, the nonmagnetic layer16 is formed on the entire top surface of the layered structure. Next,the nonmagnetic layer 16 is polished by CMP, for example, so that thefirst layer 13A and the yoke layer 15 are exposed, and the top surfacesof the first layer 13A, the yoke layer 15 and the nonmagnetic layer 16are flattened.

Next, as in the step illustrated in FIG. 17A to FIG. 17C of the firstembodiment, the protection layer 17 is formed to cover the entire topsurface of the layered structure. Wiring and terminals are then formedon the protection layer 17, the substrate is cut into sliders, and thesteps including polishing of the medium facing surface 30 andfabrication of flying rails are performed. The magnetic head is thuscompleted.

The shield 13 of the second embodiment incorporates the side shieldlayers 13E and 13F. As a result, according to the embodiment, it ispossible to further suppress expansion of the magnetic flux in regionson both sides of the end face of the pole layer 12 opposed to each otherin the direction of track width and to further suppress leakage fluxreaching the recording medium. It is thereby possible to furthersuppress the wide-range adjacent track erase. The remainder ofconfiguration, function and effects of the second embodiment are similarto those of the first embodiment.

MODIFICATION EXAMPLE

A modification example of the second embodiment will now be described.FIG. 30 is a front view of the medium facing surface of a magnetic headof the modification example. In the modification example, the grooves 25b and 25 c penetrate the encasing layer 25. At the bottoms of thegrooves 25 b and 25 c, the nonmagnetic film 27 has been removed and thepolishing stopper layer 28 touches the top surfaces of the third portion13C3 (not shown) and the insulating layer 24. The remainder ofconfiguration, function and effects of the modification example aresimilar to those of the magnetic head illustrated in FIG. 23 and FIG.24.

In a method of manufacturing the magnetic head of the modificationexample, the grooves 25 b and 25 c are formed to penetrate the encasinglayer 25 when the nonmagnetic layer 25P is selectively etched to formthe grooves 25 a, 25 b and 25 c. Furthermore, in the method ofmanufacturing the magnetic head of the modification example, after thenonmagnetic film 27 is formed, portions of the nonmagnetic film 27 areremoved by etching at the bottoms of the grooves 25 b and 25 c. Theremainder of steps of manufacturing the magnetic head of themodification example are the same as those of the method illustrated inFIG. 25 to FIG. 29.

It is possible to provide modification examples of the second embodimentthat are similar to the modification examples of the first embodiment.

Third Embodiment

Reference is now made to FIG. 31 to FIG. 33 to describe a magnetic headand a method of manufacturing the same of a third embodiment of theinvention. FIG. 31 is a perspective view illustrating a portion of themagnetic head of the third embodiment in a neighborhood of the mediumfacing surface. FIG. 32 is a cross-sectional view of the magnetic headof the embodiment. FIG. 32 illustrates a cross section orthogonal to themedium facing surface and a surface of the substrate. The arrowindicated with T in FIG. 32 shows the direction of travel of a recordingmedium. FIG. 33 is a front view of the medium facing surface of themagnetic head of the embodiment.

In the third embodiment, the end face of the second layer 13B and theend face of the first coupling portion 13C (the first portion 13C1, thesecond portion 13C2 and the third portion 13C3) are each located in themedium facing surface 30. In the third embodiment, the pole layer 12 hasa flat top surface.

In the third embodiment, the throat height TH is the length of a portionof the first layer 13A taken in the direction orthogonal to the mediumfacing surface 30, the portion being opposed to the pole layer 12 withthe gap layer 14 disposed in between.

According to the method of manufacturing the magnetic head of the thirdembodiment, the second layer 13B, the first portion 13C1, the secondportion 13C2 and the third portion 13C3 are formed such that theirrespective end faces are located in the medium facing surface 30.

According to the method of the third embodiment, as in the stepillustrated in FIG. 13A to FIG. 13C of the first embodiment, the topsurfaces of the polishing stopper layer 28 and the magnetic layer 12Pare flattened, and then a portion of the polishing stopper layer 28exposed in the top surface of the layered structure is selectivelyremoved by a method such as reactive ion etching, ion beam etching orwet etching. Next, the nonmagnetic film 27, the polishing stopper layer28 and the magnetic layer 12P are polished by CMP, for example, so thatthe nonmagnetic metal layer 26 is exposed, and the top surfaces of thenonmagnetic metal layer 26, the nonmagnetic film 27, the polishingstopper layer 28 and the magnetic layer 12P are thereby flattened. As aresult, the magnetic layer 12P is formed into the pole layer 12. In thethird embodiment, the step illustrated in FIG. 14A to FIG. 14C of thefirst embodiment is not performed while the gap layer 14 is formed onthe flattened top surface of the nonmagnetic metal layer 26, thenonmagnetic film 27, the polishing stopper layer 28 and the pole layer12.

The remainder of configuration, function and effects of the thirdembodiment are similar to those of the first embodiment.

MODIFICATION EXAMPLE

A modification example of the third embodiment will now be described.FIG. 34 is a front view of the medium facing surface of a magnetic headof the modification example. The shield 13 of the modification exampleincorporates the side shield layers 13E and 13F as in the secondembodiment. The encasing layer 25 has the grooves 25 b and 25 c inaddition to the groove 25 a, wherein the grooves 25 b and 25 c open inthe top surface of the encasing layer 25 and accommodate the side shieldlayers 13E and 13F. The nonmagnetic metal layer 26 has the openings 26 band 26 c in addition to the opening 26 a. The edges of the openings 26 band 26 c are located directly above the edges of the grooves 25 b and 25c in the top surface of the encasing layer 25, respectively. Thenonmagnetic film 27 and the polishing stopper layer 28 are located inthe groove 25 b and the opening 26 b and in the groove 25 c and theopening 26 c, in addition to the groove 25 a and the opening 26 a. Thenonmagnetic film 27 is disposed to touch the surfaces of the grooves 25b and 25 c. The side shield layers 13E and 13F are disposed apart fromthe surfaces of the grooves 25 b and 25 c. The polishing stopper layer28 is disposed between the nonmagnetic film 27 and the side shieldlayers 13E and 13F. The remainder of configuration, function and effectsof the magnetic head of the modification example are similar to those ofthe magnetic head shown in FIG. 31 to FIG. 33.

It is possible to provide a modification example of the third embodimentthat is similar to each of the modification examples of the firstembodiment or the modification example of the second embodiment.

Fourth Embodiment

A magnetic head and a method of manufacturing the same of a fourthembodiment of the invention will now be described. Reference is now madeto FIG. 35 and FIG. 36 to describe the configuration of the magnetichead of the embodiment. FIG. 35 is a cross-sectional view of themagnetic head of the embodiment. FIG. 35 illustrates a cross sectionorthogonal to the medium facing surface and a surface of the substrate.The arrow indicated with T in FIG. 35 shows the direction of travel of arecording medium. FIG. 36 is a front view of the medium facing surfaceof the magnetic head of the embodiment.

The magnetic head of the fourth embodiment comprises an insulating layer61 made of an insulating material and an encasing layer 64 made of anonmagnetic material that are provided in place of the encasing layer 25of the first embodiment. The insulating layer 61 is disposed on theflattened top surfaces of the third portion 13C3, the second couplingportion 13D, the coil 11, and the insulating layers 23 and 24. Theencasing layer 64 is disposed on the insulating layer 61. The insulatinglayer 61 and the encasing layer 64 may be made of alumina, for example.

In the fourth embodiment, as in the second embodiment, the shield 13incorporates the first side shield layer 13E and the second side shieldlayer 13F connected to the first layer 13A and disposed on both sides ofthe pole layer 12 opposed to each other in the direction of track width.Each of the side shield layers 13E and 13F has an end face located inthe medium facing surface 30. Each of the side shield layers 13E and 13Fis made of a magnetic material. The material of the side shield layers13E and 13F may be the same as that of the pole layer 12.

The encasing layer 64 has grooves 64 a, 64 b and 64 c for accommodatingthe pole layer 12 and the side shield layers 13E and 13F, respectively.The grooves 64 a, 64 b and 64 c penetrate the encasing layer 64.

The magnetic head of the fourth embodiment comprises a nonmagnetic film63 in place of the nonmagnetic film 27 of the first embodiment. Themagnetic head of the fourth embodiment does not comprise the polishingstopper layer 28 of the first embodiment. The nonmagnetic film 63 ismade of a nonmagnetic material and disposed in the grooves 64 a, 64 band 64 c to touch the surfaces of the grooves 64 a, 64 b and 64 c. Thematerial and thickness of the nonmagnetic film 63 are the same as thoseof the nonmagnetic film 27.

The pole layer 12 and the side shield layers 13E and 13F are disposedapart from the surfaces of the grooves 64 a, 64 b and 64 c,respectively. The nonmagnetic film 63 is disposed between the surface ofthe groove 64 a and the pole layer 12, and between the respectivesurfaces of the grooves 64 b, 64 c and the side shield layers 13E, 13F.

The magnetic head of the fourth embodiment comprises a polishing stopperlayer 65 disposed between the encasing layer 64 and the first layer 13Ain a region around the pole layer 12 and the side shield layers 13E and13F. The material of the polishing stopper layer 65 is the same as thatof the polishing stopper layer 28 of the first embodiment.

In the fourth embodiment, the pole layer 12 has a flat top surface. Inthe fourth embodiment, the throat height TH is the length of a portionof the first layer 13A taken in the direction orthogonal to the mediumfacing surface 30, the portion being opposed to the pole layer 12 withthe gap layer 14 disposed in between.

Reference is now made to FIG. 37 to FIG. 42 to describe a method ofmanufacturing the magnetic head of the fourth embodiment. FIG. 37 toFIG. 42 are cross-sectional views of layered structures obtained inmanufacturing process of the magnetic head. FIG. 37 to FIG. 42 showcross sections of portions of the layered structures near the mediumfacing surface, the cross sections being parallel to the medium facingsurface. The portions closer to the substrate 1 than the top shieldlayer 7 are omitted in FIG. 37 to FIG. 42.

The method of manufacturing the magnetic head of the fourth embodimentincludes the steps up to the step of flattening the top surfaces of thethird portion 13C3, the second coupling portion 13D, the coil 11, andthe insulating layers 23 and 24 as shown in FIG. 8A to FIG. 8C that arethe same as those of the first embodiment.

FIG. 37 illustrates the following step. In the step, first, theinsulating layer 61 is formed on the entire top surface of the layeredstructure. Next, the insulating layer 61 is selectively etched in aregion where the first portion 13C1 and the second portion 13C2 will bedisposed later and in a region above the second coupling portion 13D.Next, although not shown, the first portion 13C1 and the second portion13C2 are formed on the third portion 13C3 by frame plating, for example.

Next, a photoresist layer 62 is formed on the entire top surface of thelayered structure. Next, three grooves are formed in the photoresistlayer 62 in regions where the pole layer 12 and the side shield layers13E and 13F will be disposed later. Next, the nonmagnetic film 63 isformed on the entire top surface of the layered structure. Thenonmagnetic film 63 is formed by a method the same as the method offorming the nonmagnetic film 27 of the first embodiment. Next, a portionof the nonmagnetic film 63 located on the second coupling portion 13D isselectively etched.

Next, the magnetic layer 12P to be the pole layer 12 and the side shieldlayers 13E and 13F is formed on the entire top surface of the layeredstructure. The magnetic layer 12P is formed by a method the same as thatof the first embodiment. Next, the coating layer 32 made of alumina, forexample, and having a thickness of 0.5 to 1.2 μm, for example, is formedon the entire top surface of the layered structure.

Next, as shown in FIG. 38, the coating layer 32 and the magnetic layer12P are polished by CMP, for example, so that the nonmagnetic film 63 isexposed, and the top surfaces of the nonmagnetic film 63 and themagnetic layer 12P are thereby flattened.

Next, as shown in FIG. 39, the nonmagnetic film 63 and the magneticlayer 12P are slightly etched by ion beam etching, for example, suchthat a portion of the nonmagnetic film 63 located on the photoresistlayer 62 is removed. The pole layer 12 and the side shield layers 13Eand 13F are thereby formed of the portions of the magnetic layer 12Premaining after this etching.

FIG. 40 illustrates the following step. In the step, first, thephotoresist layer 62 is removed. Next, a nonmagnetic layer 64P that willbe the encasing layer 64 later is formed on the entire top surface ofthe layered structure, wherein the nonmagnetic layer 64P is formed tohave a thickness equal to the value obtained by subtracting thethickness of the polishing stopper layer 65 to be formed later from thesum of a desired thickness of the pole layer 12 and the thickness of thenonmagnetic film 63. Next, the polishing stopper layer 65 is formed bysputtering, for example, on a region of the nonmagnetic layer 64P aroundthe pole layer 12 and the side shied layers 13E and 13F. Next, a coatinglayer 66 of alumina, for example, is formed on the entire top surface ofthe layered structure by sputtering, for example.

Next, as shown in FIG. 41, the coating layer 66 and the nonmagneticlayer 64P are polished by CMP, for example, so that the polishingstopper layer 65 is exposed, and the top surfaces of the polishingstopper layer 65, the nonmagnetic layer 64P, the pole layer 12, and theside shield layers 13E and 13F are thereby flattened. The nonmagneticlayer 64P polished is formed into the encasing layer 64.

FIG. 42 illustrates the following step. In the step, first, as in thestep illustrated in FIG. 28 of the second embodiment, the gap layer 14is formed and then selectively etched, using the mask 34. As a result,the top surfaces of the first portion 13C1, the second portion 13C2, andthe side shield layers 13E and 13F are exposed, and a portion of the topsurface of the pole layer 12 is exposed. Next, the mask 34 is removed.

Next, as in the step illustrated in FIG. 29 of the second embodiment,the first layer 13A is formed on the first portion 13C1, the secondportion 13C2 and the gap layer 14. At the same time, the yoke layer 15is formed on the pole layer 12. The first layer 13A touches the topsurfaces of the side shield layers 13E and 13F. Next, as in the stepillustrated in FIG. 16A to FIG. 16C of the first embodiment, thenonmagnetic layer 16 is formed on the entire top surface of the layeredstructure. Next, the nonmagnetic layer 16 is polished by CMP, forexample, so that the first layer 13A and the yoke layer 15 are exposed,and the top surfaces of the first layer 13A, the yoke layer 15 and thenonmagnetic layer 16 are flattened.

Next, as in the step illustrated in FIG. 17A to FIG. 17C of the firstembodiment, the protection layer 17 is formed to cover the entire topsurface of the layered structure. Wiring and terminals are then formedon the protection layer 17, the substrate is cut into sliders, and thesteps including polishing of the medium facing surface 30 andfabrication of flying rails are performed. The magnetic head is thuscompleted.

As in the second embodiment, the shield 13 of the fourth embodimentincorporates the side shield layers 13E and 13F. As a result, accordingto the embodiment, it is possible to further suppress expansion of themagnetic flux in regions on both sides of the end face of the pole layer12 opposed to each other in the direction of track width and to furthersuppress leakage flux reaching the recording medium. It is therebypossible to further suppress the wide-range adjacent track erase. Theremainder of configuration, function and effects of the fourthembodiment are similar to those of the first embodiment. It is possibleto provide a modification example of the fourth embodiment similar tothe second modification example of the first embodiment.

The present invention is not limited to the foregoing embodiments butmay be practiced in still other ways. For example, in any of the first,second and fourth embodiments, the end face of the second layer 13B andthe end face of the first coupling portion 13C (the first portion 13C1,the second portion 13C2 and the third portion 13C3) may be located inthe medium facing surface 30 as in the second embodiment.

In the invention the pole layer may have a penetrating hole, and thefirst coupling portion of the shield may pass through this hole withouttouching the pole layer and couple the first layer to the second layer.

The pole layer of the invention is not limited to the one formed in themanner disclosed in each of the embodiments but may be formed otherwise.For example, the pole layer may be formed by patterning a magnetic layerby etching, or may be formed by plating.

While the magnetic head disclosed in each of the embodiments has such aconfiguration that the read head is formed on the base body and thewrite head is stacked on the read head, it is also possible that theread head is stacked on the write head.

Obviously many modifications and variations of the present invention arepossible in the light of the above teachings. It is therefore to beunderstood that within the scope of the appended claims the inventionmay be practiced otherwise than as specifically described.

1. A magnetic head for perpendicular magnetic recording comprising: amedium facing surface that faces toward a recording medium; a coil forgenerating a magnetic field corresponding to data to be written on therecording medium; a pole layer having an end face located in the mediumfacing surface, allowing a magnetic flux corresponding to the fieldgenerated by the coil to pass therethrough, and generating a writemagnetic field for writing the data on the recording medium by means ofa perpendicular magnetic recording system; and a shield, wherein: theshield incorporates: a first layer having an end face located in aregion of the medium facing surface forward of the end face of the polelayer along a direction of travel of the recording medium; a secondlayer disposed in a region sandwiching the pole layer with the firstlayer; a first coupling portion coupling the first layer to the secondlayer without touching the pole layer; and a second coupling portioncoupling the pole layer to the second layer and located farther from themedium facing surface than the first coupling portion; the magnetic headfurther comprises a gap layer made of a nonmagnetic material anddisposed between the pole layer and the first layer; in the mediumfacing surface, the end face of the first layer is located at a specificdistance created by a thickness of the gap layer from the end face ofthe pole layer; the end face of the pole layer has a side locatedadjacent to the gap layer, the side defining a track width; part of thecoil passes through a space surrounded by the pole layer, the secondlayer, the first coupling portion and the second coupling portion; thefirst coupling portion couples the first layer to the second layer onboth sides of the pole layer opposed to each other in a direction oftrack width, the first coupling portion incorporating: a first portionand a second portion that are connected to the first layer and disposedon both sides of the pole layer opposed to each other in the directionof track width; and a third portion coupling the second layer to thefirst and second portions and disposed between the medium facing surfaceand the part of the coil; and the first layer is coupled to the polelayer through the first coupling portion, the second layer and thesecond coupling portion only, wherein the first coupling portion, thesecond layer and the second coupling portion form only one magnetic pathfor passing a magnetic flux between the first layer and the pole layer.2. The magnetic head according to claim 1, wherein the gap layer has athickness that falls within a range of 5 to 60 nm inclusive.
 3. Themagnetic head according to claim 1, wherein each of the second layer andthe first coupling portion has an end face located in the medium facingsurface.
 4. The magnetic head according to claim 1, wherein the secondlayer has an end face closer to the medium facing surface, the end facebeing located at a distance from the medium facing surface.
 5. Themagnetic head according to claim 1, wherein the first coupling portionhas an end face closer to the medium facing surface, the end face beinglocated at a distance from the medium facing surface.
 6. The magnetichead according to claim 1, wherein the shield further incorporates afirst side shield layer and a second side shield layer that areconnected to the first layer and disposed on both sides of the polelayer opposed to each other in a direction of track width; and each ofthe first and second side shield layers has an end face located in themedium facing surface.
 7. The magnetic head according to claim 1,wherein the coil has a shape of flat whorl wound around the secondcoupling portion.
 8. The magnetic head according to claim 1, wherein thecoil has a helical shape wound around the pole layer.
 9. The magnetichead according to claim 1, further comprising: an encasing layer made ofa nonmagnetic material and having a groove that opens in a top surfacethereof and accommodates at least part of the pole layer; and anonmagnetic conductive layer made of a nonmagnetic conductive materialand disposed in the groove of the encasing layer between the encasinglayer and the pole layer.
 10. The magnetic head according to claim 1,wherein: the pole layer has a surface that bends, the surface touchingthe gap layer; and the gap layer bends along the surface of the polelayer that bends.
 11. The magnetic head according to claim 1, wherein:the first layer incorporates: a middle portion including a portionfacing toward the pole layer with the gap layer disposed in between; andtwo side portions located at positions outside the middle portion alonga direction of track width; and a maximum length of each of the sideportions taken in a direction orthogonal to the medium facing surface isgreater than a length of the middle portion taken in the directionorthogonal to the medium facing surface.
 12. A method of manufacturing amagnetic head for perpendicular magnetic recording, the magnetic headcomprising: a medium facing surface that faces toward a recordingmedium; a coil for generating a magnetic field corresponding to data tobe written on the recording medium; a pole layer having an end facelocated in the medium facing surface, allowing a magnetic fluxcorresponding to the field generated by the coil to pass therethrough,and generating a write magnetic field for writing the data on therecording medium by means of a perpendicular magnetic recording system;and a shield, wherein: the shield incorporates: a first layer having anend face located in a region of the medium facing surface forward of theend face of the pole layer along a direction of travel of the recordingmedium; a second layer disposed in a region sandwiching the pole layerwith the first layer; a first coupling portion coupling the first layerto the second layer without touching the pole layer; and a secondcoupling portion coupling the pole layer to the second layer and locatedfarther from the medium facing surface than the first coupling portion;the magnetic head further comprises a gap layer made of a nonmagneticmaterial and disposed between the pole layer and the first layer; in themedium facing surface, the end face of the first layer is located at aspecific distance created by a thickness of the gap layer from the endface of the pole layer; the end face of the pole layer has a sidelocated adjacent to the gap layer, the side defining a track width; andpart of the coil passes through a space surrounded by the pole layer,the second layer, the first coupling portion and the second couplingportion; the first coupling portion couples the first layer to thesecond layer on both sides of the pole layer opposed to each other in adirection of track width, the first coupling portion incorporating: afirst portion and a second portion that are connected to the first layerand disposed on both sides of the pole layer opposed to each other inthe direction of track width; and a third portion coupling the secondlayer to the first and second portions and disposed between the mediumfacing surface and the part of the coil; and the first layer is coupledto the pole layer through the first coupling portions, the second layerand the second coupling portion only, wherein the first couplingportion, the second layer and the second coupling portion form only onemagnetic path for passing a magnetic flux between the first layer andthe pole layer, the method comprising the steps of: forming the secondlayer; forming the coil; forming the first and second coupling portions;forming the pole layer; forming the gap layer on the pole layer; andforming the first layer on the gap layer.
 13. The method according toclaim 12, wherein the gap layer has a thickness that falls within arange of 5 to 60 nm inclusive.
 14. The method according to claim 12,wherein each of the second layer and the first coupling portion has anend face located in the medium facing surface.
 15. The method accordingto claim 12, wherein the second layer has an end face closer to themedium facing surface, the end face being located at a distance from themedium facing surface.
 16. The method according to claim 12, wherein thefirst coupling portion has an end face closer to the medium facingsurface, the end face being located at a distance from the medium facingsurface.
 17. The method according to claim 12, wherein the shieldfurther incorporates a first side shield layer and a second side shieldlayer that are connected to the first layer and disposed on both sidesof the pole layer opposed to each other in a direction of track width;and each of the first and second side shield layers has an end facelocated in the medium facing surface, the method further comprising thestep of forming the first and second side shield layers performedbetween the step of forming the second layer and the step of forming thegap layer.
 18. The method according to claim 12, wherein the coil has ashape of flat whorl wound around the second coupling portion.
 19. Themethod according to claim 12, wherein the coil has a helical shape woundaround the pole layer.
 20. The method according to claim 12, wherein themagnetic head further comprises: an encasing layer made of a nonmagneticmaterial and having a groove that opens in a top surface thereof andaccommodates at least part of the pole layer; and a nonmagneticconductive layer made of a nonmagnetic conductive material and disposedin the groove of the encasing layer between the encasing layer and thepole layer, the method further comprising the steps of forming theencasing layer and forming the nonmagnetic conductive layer.
 21. Themethod according to claim 20, wherein the nonmagnetic conductive layeris formed by chemical vapor deposition in which formation of a singleatomic layer is repeated.
 22. The method according to claim 21, whereinthe nonmagnetic conductive material is Ta or Ru.
 23. The methodaccording to claim 12, wherein: the pole layer has a surface that bends,the surface touching the gap layer; and the gap layer bends along thesurface of the pole layer that bends.
 24. The method according to claim23, wherein the gap layer is formed by chemical vapor deposition inwhich formation of a single atomic layer is repeated.
 25. The methodaccording to claim 24, wherein the nonmagnetic material forming the gaplayer is Ta, Ru or Al₂O₃.
 26. The method according to claim 12, wherein:the first layer incorporates: a middle portion including a portionfacing toward the pole layer with the gap layer disposed in between; andtwo side portions located at positions outside the middle portion alonga direction of track width; and a maximum length of each of the sideportions taken in a direction orthogonal to the medium facing surface isgreater than a length of the middle portion taken in the directionorthogonal to the medium facing surface.
 27. A magnetic head forperpendicular magnetic recording comprising: a medium facing surfacethat faces toward a recording medium; a coil for generating a magneticfield corresponding to data to be written on the recording medium; apole layer having an end face located in the medium facing surface,allowing a magnetic flux corresponding to the field generated by thecoil to pass therethrough, and generating a write magnetic field forwriting the data on the recording medium by means of a perpendicularmagnetic recording system; and a shield, wherein: the shieldincorporates: a first layer having an end face located in a region ofthe medium facing surface forward of the end face of the pole layeralong a direction of travel of the recording medium; a second layerdisposed in a region sandwiching the pole layer with the first layer; afirst coupling portion coupling the first layer to the second layerwithout touching the pole layer; and a second coupling portion couplingthe pole layer to the second layer and located farther from the mediumfacing surface than the first coupling portion; the magnetic headfurther comprises a gap layer made of a nonmagnetic material anddisposed between the pole layer and the first layer; in the mediumfacing surface, the end face of the first layer is located at a specificdistance created by a thickness of the gap layer from the end face ofthe pole layer; the end face of the pole layer has a side locatedadjacent to the gap layer, the side defining a track width; part of thecoil passes through a space surrounded by the pole layer, the secondlayer, the first coupling portion and the second coupling portion; thefirst coupling portion incorporates: a first portion and a secondportion that are connected to the first layer and disposed on both sidesof the pole layer opposed to each other in a direction of track width;and a third portion coupling the second layer to the first and secondportions and disposed between the medium facing surface and the part ofthe coil; and the first coupling portion couples the first layer to thesecond layer on both sides of the pole layer opposed to each other inthe direction of track width.
 28. A method of manufacturing a magnetichead for perpendicular magnetic recording, the magnetic head comprising:a medium facing surface that faces toward a recording medium; a coil forgenerating a magnetic field corresponding to data to be written on therecording medium; a pole layer having an end face located in the mediumfacing surface, allowing a magnetic flux corresponding to the fieldgenerated by the coil to pass therethrough, and generating a writemagnetic field for writing the data on the recording medium by means ofa perpendicular magnetic recording system; and a shield, wherein: theshield incorporates: a first layer having an end face located in aregion of the medium facing surface forward of the end face of the polelayer along a direction of travel of the recording medium; a secondlayer disposed in a region sandwiching the pole layer with the firstlayer; a first coupling portion coupling the first layer to the secondlayer without touching the pole layer; and a second coupling portioncoupling the pole layer to the second layer and located farther from themedium facing surface than the first coupling portion; the magnetic headfurther comprises a gap layer made of a nonmagnetic material anddisposed between the pole layer and the first layer; in the mediumfacing surface, the end face of the first layer is located at a specificdistance created by a thickness of the gap layer from the end face ofthe pole layer; the end face of the pole layer has a side locatedadjacent to the gap layer, the side defining a track width; and part ofthe coil passes through a space surrounded by the pole layer, the secondlayer, the first coupling portion and the second coupling portion, themethod comprising the steps of: forming the second layer; forming thecoil; forming the first and second coupling portions; forming the polelayer; forming the gap layer on the pole layer; and forming the firstlayer on the gap layer, wherein: the first coupling portionincorporates: a first portion and a second portion that are connected tothe first layer and disposed on both sides of the pole layer opposed toeach other in a direction of track width; and a third portion couplingthe second layer to the first and second portions and disposed betweenthe medium facing surface and the part of the coil; and the firstcoupling portion couples the first layer to the second layer on bothsides of the pole layer opposed to each other in the direction of trackwidth.